Network Working Group                                          D. Burdett
Request for Comments: 2801                                   Commerce One
Category: Informational                                        April 2000


                Internet Open Trading Protocol - IOTP
                             Version 1.0

Status of this Memo

  This memo provides information for the Internet community.  It does
  not specify an Internet standard of any kind.  Distribution of this
  memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

  The Internet Open Trading Protocol (IOTP) provides an interoperable
  framework for Internet commerce. It is payment system independent and
  encapsulates payment systems such as SET, Secure Channel
  Credit/Debit, Mondex, CyberCoin, GeldKarte, etc. IOTP is able to
  handle cases where such merchant roles as the shopping site, the
  Payment Handler, the Delivery Handler of goods or services, and the
  provider of customer support are performed by different parties or by
  one party.

Table of Contents

  1.  Background .....................................................7
    1.1  Commerce on the Internet, a Different Model .................7
    1.2  Benefits of IOTP ............................................9
    1.3  Baseline IOTP ..............................................10
    1.4  Objectives of Document .....................................10
    1.5  Scope of Document ..........................................11
    1.6  Document Structure .........................................11
    1.7  Intended Readership ........................................13
        1.7.1  Reading Guidelines ...................................13
  2.  Introduction ..................................................14
    2.1  Trading Roles ..............................................16
    2.2  Trading Exchanges ..........................................18
        2.2.1  Offer Exchange .......................................19
        2.2.2  Payment Exchange .....................................21
        2.2.3  Delivery Exchange ....................................24
        2.2.4  Authentication Exchange ..............................26
    2.3  Scope of Baseline IOTP .....................................28



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RFC 2801                       IOTP/1.0                       April 2000


  3.  Protocol Structure ............................................31
    3.1  Overview ...................................................32
        3.1.1  IOTP Message Structure ...............................32
        3.1.2  IOTP Transactions ....................................34
    3.2  IOTP Message ...............................................35
        3.2.1  XML Document Prolog ..................................37
    3.3  Transaction Reference Block ................................37
        3.3.1  Transaction Id Component .............................38
        3.3.2  Message Id Component .................................39
        3.3.3  Related To Component .................................41
    3.4  ID Attributes ..............................................42
        3.4.1  IOTP Message ID Attribute Definition .................43
        3.4.2  Block and Component ID Attribute Definitions .........44
        3.4.3  Example of use of ID Attributes ......................46
    3.5  Element References .........................................46
    3.6  Extending IOTP .............................................48
        3.6.1  Extra XML Elements ...................................49
        3.6.2  Opaque Embedded Data .................................50
    3.7  Packaged Content Element ...................................50
        3.7.1  Packaging HTML .......................................52
        3.7.2  Packaging XML ........................................53
    3.8  Identifying Languages ......................................54
    3.9  Secure and Insecure Net Locations ..........................54
    3.10 Cancelled Transactions .....................................55
        3.10.1 Cancelling Transactions ..............................55
        3.10.2 Handling Cancelled Transactions ......................56
  4.  IOTP Error Handling ...........................................56
    4.1  Technical Errors ...........................................57
    4.2  Business Errors ............................................57
    4.3  Error Depth ................................................58
        4.3.1  Transport Level ......................................58
        4.3.2  Message Level ........................................58
        4.3.3  Block Level ..........................................59
    4.4  Idempotency, Processing Sequence, and Message Flow .........61
    4.5  Server Role Processing Sequence ............................62
        4.5.1  Initiating Transactions ..............................62
        4.5.2  Processing Input Messages ............................63
        4.5.3  Cancelling a Transaction .............................70
        4.5.4  Retransmitting Messages ..............................70
    4.6  Client Role Processing Sequence ............................71
        4.6.1  Initiating Transactions ..............................71
        4.6.2  Processing Input Messages ............................72
        4.6.3  Cancelling a Transaction .............................74
        4.6.4  Retransmitting Messages ..............................74
  5.  Security Considerations .......................................74
    5.1  Determining whether to use digital signatures ..............74
    5.2  Symmetric and Asymmetric Cryptography ......................76
    5.3  Data Privacy ...............................................77



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RFC 2801                       IOTP/1.0                       April 2000


    5.4  Payment Protocol Security ..................................77
  6.  Digital Signatures and IOTP ...................................77
    6.1  How IOTP uses Digital Signatures ...........................77
        6.1.1  IOTP Signature Example ...............................80
        6.1.2  OriginatorInfo and RecipientInfo Elements ............82
        6.1.3  Using signatures to Prove Actions Complete
               Successfully .........................................83
    6.2  Checking a Signature is Correctly Calculated ...............84
    6.3  Checking a Payment or Delivery can occur ...................85
        6.3.1  Check Request Block sent Correct Organisation ........86
        6.3.2  Check Correct Components present in Request Block ....91
        6.3.3  Check an Action is Authorised ........................91
  7.  Trading Components ............................................93
    7.1  Protocol Options Component .................................96
    7.2  Authentication Request Component ...........................97
    7.3  Authentication Response Component ..........................98
    7.4  Trading Role Information Request Component .................99
    7.5  Order Component ...........................................100
        7.5.1  Order Description Content ...........................101
        7.5.2  OkFrom and OkTo Timestamps ..........................101
    7.6  Organisation Component ....................................102
        7.6.1  Organisation IDs ....................................104
        7.6.2  Trading Role Element ................................105
        7.6.3  Contact Information Element .........................108
        7.6.4  Person Name Element .................................109
        7.6.5  Postal Address Element ..............................110
    7.7  Brand List Component ......................................111
        7.7.1  Brand Element .......................................113
        7.7.2  Protocol Brand Element ..............................115
        7.7.3  Protocol Amount Element .............................116
        7.7.4  Currency Amount Element .............................117
        7.7.5  Pay Protocol Element ................................118
    7.8  Brand Selection Component .................................120
        7.8.1  Brand Selection Brand Info Element ..................122
        7.8.2  Brand Selection Protocol Amount Info Element ........122
        7.8.3  Brand Selection Currency Amount Info Element ........123
    7.9  Payment Component .........................................123
    7.10 Payment Scheme Component ..................................125
    7.11 Payment Receipt Component .................................126
    7.12 Payment Note Component ....................................128
    7.13 Delivery Component ........................................129
        7.13.1 Delivery Data Element ...............................130
    7.14 Consumer Delivery Data Component ..........................132
    7.15 Delivery Note Component ...................................133
    7.16 Status Component ..........................................134
        7.16.1 Offer Completion Codes ..............................137
        7.16.2 Payment Completion Codes ............................138
        7.16.3 Delivery Completion Codes ...........................140



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RFC 2801                       IOTP/1.0                       April 2000


        7.16.4 Authentication Completion Codes .....................142
        7.16.5 Undefined Completion Codes ..........................144
        7.16.6 Transaction Inquiry Completion Codes ................144
    7.17 Trading Role Data Component ...............................144
        7.17.1 Who Receives a Trading Role Data Component ..........145
    7.18 Inquiry Type Component ....................................146
    7.19 Signature Component .......................................147
        7.19.1 IOTP usage of signature elements and attributes .....148
        7.19.2 Offer Response Signature Component ..................150
        7.19.3 Payment Receipt Signature Component .................151
        7.19.4 Delivery Response Signature Component ...............152
        7.19.5 Authentication Request Signature Component ..........152
        7.19.6 Authentication Response Signature Component .........153
        7.19.7 Inquiry Request Signature Component .................153
        7.19.8 Inquiry Response Signature Component ................153
        7.19.9 Ping Request Signature Component ....................153
        7.19.10 Ping Response Signature Component...................154
    7.20 Certificate Component .....................................154
        7.20.1 IOTP usage of signature elements and attributes .....154
    7.21 Error Component ...........................................154
        7.21.1 Error Processing Guidelines .........................157
        7.21.2 Error Codes .........................................158
        7.21.3 Error Location Element ..............................162
  8.  Trading Blocks ...............................................163
    8.1  Trading Protocol Options Block ............................166
    8.2  TPO Selection Block .......................................167
    8.3  Offer Response Block ......................................168
    8.4  Authentication Request Block ..............................169
    8.5  Authentication Response Block .............................170
    8.6  Authentication Status Block ...............................171
    8.7  Payment Request Block .....................................171
    8.8  Payment Exchange Block ....................................173
    8.9  Payment Response Block ....................................173
    8.10 Delivery Request Block ....................................175
    8.11 Delivery Response Block ...................................176
    8.12 Inquiry Request Trading Block .............................177
    8.13 Inquiry Response Trading Block ............................177
    8.14 Ping Request Block ........................................179
    8.15 Ping Response Block .......................................179
    8.16 Signature Block ...........................................181
        8.16.1 Signature Block with Offer Response .................182
        8.16.2 Signature Block with Payment Request ................182
        8.16.3 Signature Block with Payment Response ...............182
        8.16.4 Signature Block with Delivery Request ...............182
        8.16.5 Signature Block with Delivery Response ..............182
    8.17 Error Block ...............................................183
    8.18 Cancel Block ..............................................184
  9.  Internet Open Trading Protocol Transactions ..................184



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RFC 2801                       IOTP/1.0                       April 2000


    9.1  Authentication and Payment Related IOTP Transactions ......185
        9.1.1  Authentication Document Exchange ....................188
        9.1.2  Offer Document Exchange .............................194
        9.1.3  Payment Document Exchange ...........................203
        9.1.4  Delivery Document Exchange ..........................209
        9.1.5  Payment and Delivery Document Exchange ..............212
        9.1.6  Baseline Authentication IOTP Transaction ............216
        9.1.7  Baseline Deposit IOTP Transaction ...................218
        9.1.8  Baseline Purchase IOTP Transaction ..................220
        9.1.9  Baseline Refund IOTP Transaction ....................222
        9.1.10 Baseline Withdrawal IOTP Transaction ................224
        9.1.11 Baseline Value Exchange IOTP Transaction ............226
        9.1.12 Valid Combinations of Document Exchanges ............230
        9.1.13 Combining Authentication Transactions with other
               Transactions ........................................234
    9.2  Infrastructure Transactions ...............................235
        9.2.1  Baseline Transaction Status Inquiry IOTP Transaction 235
        9.2.2  Baseline Ping IOTP Transaction ......................241
  10. Retrieving Logos .............................................244
    10.1 Logo Size .................................................245
    10.2 Logo Color Depth ..........................................245
    10.3 Logo Net Location Examples ................................246
  11. Brands .......................................................246
    11.1 Brand Definitions and Brand Selection .....................246
        11.1.1 Definition of Payment Instrument ....................247
        11.1.2 Definition of Brand .................................247
        11.1.3 Definition of Dual Brand ............................248
        11.1.4 Definition of Promotional Brand .....................248
        11.1.5 Identifying Promotional Brands ......................249
    11.2 Brand List Examples .......................................251
        11.2.1 Simple Credit Card Based Example ....................252
        11.2.2 Credit Card Brand List Including Promotional Brands..253
        11.2.3 Brand Selection Example .............................254
        11.2.4 Complex Electronic Cash Based Brand List ............255
  12. IANA Considerations ..........................................257
    12.1 Codes Controlled by IANA ..................................257
    12.2 Codes not controlled by IANA ..............................263
  13. Internet Open Trading Protocol Data Type Definition ..........263
  14. Glossary .....................................................277
  15. References ...................................................284
  16. Author's Address .............................................287
  17. Full Copyright Statement .....................................290









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RFC 2801                       IOTP/1.0                       April 2000


Table of Figures

  Figure 1 IOTP Trading Roles                                       16
  Figure 2 Offer Exchange                                           19
  Figure 3 Payment Exchange                                         22
  Figure 4 Delivery Exchange                                        25
  Figure 5 Authentication Exchange                                  27
  Figure 6 IOTP Message Structure                                   33
  Figure 7 An IOTP Transaction                                      34
  Figure 8 Example use of ID attributes                             46
  Figure 9 Element References                                       48
  Figure 10 Signature Digests                                       79
  Figure 11 Example use of Signatures for Baseline Purchase         81
  Figure 12 Checking a Payment Handler can carry out a Payment      87
  Figure 13 Checking a Delivery Handler can carry out a Delivery    90
  Figure 14 Trading Components                                      94
  Figure 15 Brand List Element Relationships                       113
  Figure 16 Trading Blocks                                         164
  Figure 17 Payment and Authentication Message Flow Combinations   187
  Figure 18 Authentication Document Exchange                       190
  Figure 19 Brand Dependent Offer Document Exchange                196
  Figure 20 Brand Independent Offer Exchange                       198
  Figure 21 Payment Document Exchange                              204
  Figure 22 Delivery Document Exchange                             210
  Figure 23 Payment and Delivery Document Exchange                 214
  Figure 24 Baseline Authentication IOTP Transaction               217
  Figure 25 Baseline Deposit IOTP Transaction                      219
  Figure 26 Baseline Purchase IOTP Transaction                     221
  Figure 27 Baseline Refund IOTP Transaction                       223
  Figure 28 Baseline Withdrawal IOTP Transaction                   225
  Figure 29 Baseline Value Exchange IOTP Transaction               228
  Figure 30 Baseline Value Exchange Signatures                     230
  Figure 31 Valid Combinations of Document Exchanges               231
  Figure 32 Baseline Transaction Status Inquiry                    238
  Figure 33 Baseline Ping Messages                                 242
















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RFC 2801                       IOTP/1.0                       April 2000


1. Background

  The Internet Open Trading Protocol (IOTP) provides an interoperable
  framework for Internet commerce. It is payment system independent and
  encapsulates payment systems such as SET, Mondex, CyberCash,
  DigiCash, GeldKarte, etc. IOTP is able to handle cases where such
  merchant roles as the shopping site, the Payment Handler, the
  Delivery Handler of goods or services, and the provider of customer
  support are performed by different parties or by one party.

  The developers of IOTP seek to provide a virtual capability that
  safely replicates the real world, the paper based, traditional,
  understood, accepted methods of trading, buying, selling, value
  exchanging that has existed for many hundreds of years.  The
  negotiation of who will be the parties to the trade, how it will be
  conducted, the presentment of an offer, the method of payment, the
  provision of a payment receipt, the delivery of goods and the receipt
  of goods. These are events that are taken for granted in the course
  of real world trade. IOTP has been produced to provide the same for
  the virtual world, and to prepare and provide for the introduction of
  new models of trading made possible by the expanding presence of the
  virtual world.

  The other fundamental ideal of the IOTP effort is to produce a
  definition of these trading events in such a way that no matter where
  produced, two unfamiliar parties using electronic commerce
  capabilities to buy and sell that conform to the IOTP specifications
  will be able to complete the business safely and successfully.

  In summary, IOTP supports:

  o Familiar trading models

  o New trading models

  o Global interoperability

  The remainder of this section provides background to why IOTP was
  developed. The specification itself starts in the next chapter.

1.1 Commerce on the Internet, a Different Model

  The growth of the Internet and the advent of electronic commerce are
  bringing about enormous changes around the world in society, politics
  and government, and in business. The ways in which trading partners
  communicate, conduct commerce, are governed have been enriched and
  changed forever.




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RFC 2801                       IOTP/1.0                       April 2000


  One of the very fundamental changes about which IOTP is concerned is
  taking place in the way consumers and merchants trade.
  Characteristics of trading that have changed markedly include:

  o  Presence: Face-to-face transactions become the exception, not the
     rule.  Already with the rise of mail order and telephone order
     placement this change has been felt in western commerce.
     Electronic commerce over the Internet will further expand the
     scope and volume of transactions conducted without ever seeing the
     people who are a part of the enterprise with whom one does
     business.

  o  Authentication: An important part of personal presence is the
     ability of the parties to use familiar objects and dialogue to
     confirm they are who they claim to be. The seller displays one or
     several well known financial logos that declaim his ability to
     accept widely used credit and debit instruments in the payment
     part of a purchase. The buyer brings government or financial
     institution identification that assures the seller she will be
     paid. People use intangibles such as personal appearance and
     conduct, location of the store, apparent quality and familiarity
     with brands of merchandise, and a good clear look in the eye to
     reinforce formal means of authentication.

  o  Payment Instruments: Despite the enormous size of bank card
     financial payments associations and their members, most of the
     world's trade still takes place using the coin of the realm or
     barter. The present infrastructure of the payments business cannot
     economically support low value transactions and could not survive
     under the consequent volumes of transactions if it did accept low
     value transactions.

  o  Transaction Values: New meaning for low value transactions arises
     in the Internet where sellers may wish to offer for example, pages
     of information for fractions of currency that do not exist in the
     real world.

  o  Delivery: New modes of delivery must be accommodated such as
     direct electronic delivery. The means by which receipt is
     confirmed and the execution of payment change dramatically where
     the goods or services have extremely low delivery cost but may in
     fact have very high value.  Or, maybe the value is not high, but
     once delivery occurs the value is irretrievably delivered so
     payment must be final and non-refundable but delivery nonetheless
     must still be confirmed before payment.  Incremental delivery such
     as listening or viewing time or playing time are other models that
     operate somewhat differently in the virtual world.




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1.2 Benefits of IOTP

  ELECTRONIC COMMERCE SOFTWARE VENDORS

  Electronic Commerce Software Vendors will be able to develop e-
  commerce products which are more attractive as they will inter-
  operate with any other vendors' software. However, since IOTP focuses
  on how these solutions communicate, there is still plenty of
  opportunity for product differentiation.

  PAYMENT BRANDS

  IOTP provides a standard framework for encapsulating payment
  protocols.  This means that it is easier for payment products to be
  incorporated into IOTP solutions. As a result the payment brands will
  be more widely distributed and available on a wider variety of
  platforms.

  MERCHANTS

  There are several benefits for Merchants:

  o  they will be able to offer a wider variety of payment brands,

  o  they can be more certain that the customer will have the software
     needed to complete the purchase

  o  through receiving payment and delivery receipts from their
     customers, they will be able to provide customer care knowing that
     they are dealing with the individual or organisation with which
     they originally traded

  o  new merchants will be able to enter this new (Internet) market-
     place with new products and services, using the new trading
     opportunities which IOTP presents

  BANKS AND FINANCIAL INSTITUTIONS

  There are also several benefits for Banks and Financial Institutions:

  o  they will be able to provide IOTP support for merchants

  o  they will find new opportunities for IOTP related services:

     -  providing customer care for merchants
     -  fees from processing new payments and deposits





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RFC 2801                       IOTP/1.0                       April 2000


  o  they have an opportunity to build relationships with new types of
     merchants

  CUSTOMERS

  For Customers there are several benefits:

  o  they will have a larger selection of merchants with whom they can
     trade

  o  there is a more consistent interface when making the purchase

  o  there are ways in which they can get their problems fixed through
     the merchant (rather than the bank!)

  o  there is a record of their transaction which can be used, for
     example, to feed into accounting systems or, potentially, to
     present to the tax authorities

1.3 Baseline IOTP

  This specification is Baseline IOTP. It is a Baseline in that it
  contains ways of doing trades on the Internet which are the most
  common, for example purchases and refunds.

  The group that has worked on the IOTP see an extended version being
  developed over time but feel a need to focus on a limited function
  but completely usable specification in order that implementers can
  develop solutions that work now.

  During this period it is anticipated that there will be no changes to
  the scope of this specification with the only changes made being
  limited to corrections where problems are found. Software solutions
  have been developed based on earlier versions of this specification
  (for example version 0.9 published in early 1998 and earlier
  revisions of version 1.0 published during 1999) which prove that the
  IOTP works.

1.4 Objectives of Document

  The objectives of this document are to provide a specification of
  version 1.0 of the Internet Open Trading Protocols which can be used
  to design and implement systems which support electronic trading on
  the Internet using the Internet Open Trading Protocols.







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  The purpose of the document is:

  o  to allow potential developers of products based on the protocol to
     develop software/hardware solutions which use the protocol

  o  to allow the financial services industry to understand a
     developing electronic commerce trading protocol that encapsulates
     (without modification) any of the current or developing payment
     schemes now being used or considered by their merchant customer
     base

1.5 Scope of Document

  The protocol describes the content, format and sequences of messages
  that pass among the participants in an electronic trade - consumers,
  merchants and banks or other financial institutions, and customer
  care providers.  These are required to support the electronic
  commerce transactions outlined in the objectives above.

  The protocol is designed to be applicable to any electronic payment
  scheme since it targets the complete purchase process where the
  movement of electronic value from the payer to the payee is only one,
  but important, step of many that may be involved to complete the
  trade.

  Payment Scheme which IOTP could support include MasterCard Credit,
  Visa Credit, Mondex Cash, Visa Cash, GeldKarte, eCash, CyberCoin,
  Millicent, Proton, etc.

  Each payment scheme contains some message flows which are specific to
  that scheme. These scheme-specific parts of the protocol are
  contained in a set of payment scheme supplements to this
  specification.

  The document does not prescribe the software and processes that will
  need to be implemented by each participant. It does describe the
  framework necessary for trading to take place.

  This document also does not address any legal or regulatory issues
  surrounding the implementation of the protocol or the information
  systems which use them.

1.6 Document Structure

  The document consists of the following sections:

  o  Section 1 - Background: This section gives a brief background on
     electronic commerce and the benefits IOTP offers.



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  o  Section 2 - Introduction: This section describes the various
     Trading Exchanges and shows how these trading exchanges are used
     to construct the IOTP Transactions. This section also explains
     various Trading Roles that would participate in electronic trade.

  o  Section 3 - Protocol Structure: This section summarises how
     various IOTP transactions are constructed using the Trading Blocks
     and Trading Components that are the fundamental building blocks
     for IOTP transactions. All IOTP transaction messages are well
     formed XML documents.

  o  Section 4 - IOTP Error Handling: This section describes how to
     process exceptions and errors during the protocol message exchange
     and trading exchange processing. This section provides a generic
     overview of the exception handling. This section should be read
     carefully.

  o  Section 5 - Security Considerations: This section considers from
     an IETF perspective, how IOTP addresses security. It includes: how
     to determine whether to use digital signatures with IOTP, how IOTP
     address data privacy, and how security built into payment
     protocols relate to IOTP security.

  o  Section 6 - Digital Signatures and IOTP: This section provides an
     overview of how IOTP uses digital signatures; how to check a
     signature is correctly calculated and how the various Trading
     Roles that participate in trade should check signatures when
     required.

  o  Section 7 - Trading Components: This section defines the XML
     elements required by Trading Components.

  o  Section 8 - Trading Blocks: This section describes how Trading
     Blocks are constructed from Trading Components.

  o  Section 9 - Internet Open Trading Protocol Transactions: This
     section describes all the IOTP Baseline transactions. It refers to
     Trading Blocks and Trading Components and Signatures. This section
     doesn't directly link error handling during the protocol
     exchanges, the reader is advised to understand Error Handling as
     defined in section before reading this section.

  o  Section 10 - Retrieving Logos: This section describes how IOTP
     specific logos can be retrieved.







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  o  Section 11 - Brands: This section provides: an overview of Brand
     Definitions and Brand Selection which describe how a Consumer can
     select a Brand from a list provided by the Merchant; as well as
     some examples of Brand Lists.

  o  Section 12 - IANA Considerations: This section describes how new
     values for codes used by IOTP are co-ordinated.

  o  Section 13 - Internet Open Trading Protocol Data Type Definition:
     This section contains the XML Data Type Definitions for IOTP.

  o  Section 14 - Glossary. This describes all the major terminology
     used by IOTP.

  o  Section 15 - A list of the other documents referenced by the IOTP
     specification.

  o  Section 16 - The Author's Address

  o  Section 17 - Full Copyright Statement

1.7 Intended Readership

  Software and hardware developers; development analysts; business and
  technical planners; industry analysts; merchants; bank and other
  payment handlers; owners, custodians, and users of payment protocols.

1.7.1 Reading Guidelines

  This IOTP specification is structured primarily in a sequence
  targeted at people who want to understand the principles of IOTP.
  However from practical implementation experience by implementers of
  earlier of versions of the protocol new readers who plan to implement
  IOTP may prefer to read the document in a different sequence as
  described below.

  Review the transport independent parts of the specification. This
  covers:

  o Section 14 - Glossary

  o Section 1 - Background

  o Section 2 - Introduction

  o Section 3 - Protocol Structure

  o Section 4 - IOTP Error Handling



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  o Section 5 - Security Considerations

  o Section 9 - Internet Open Trading Protocol Transactions

  o Section 11 - Brands

  o Section 12 - IANA Considerations

  o Section 10 - Retrieving Logos

  Review the detailed XML definitions:

  o Section 8 - Trading Blocks

  o Section 7 - Trading Components

  o Section 6 - Digital Signatures and IOTP

2. Introduction

  The Internet Open Trading Protocols (IOTP) define a number of
  different types of IOTP Transactions:

  o  Purchase. This supports a purchase involving an offer, a payment
     and optionally a delivery

  o  Refund. This supports the refund of a payment as a result of,
     typically, an earlier purchase

  o  Value Exchange. This involves two payments which result in the
     exchange of value from one combination of currency and payment
     method to another

  o  Authentication. This supports one organisation or individual to
     check that another organisation or individual are who they appear
     to be.

  o  Withdrawal. This supports the withdrawal of electronic cash from a
     financial institution

  o  Deposit. This supports the deposit of electronic cash at a
     financial institution

  o  Inquiry. This supports inquiries on the status of an IOTP
     transaction which is either in progress or is complete






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  o  Ping. This supports a simple query which enables one IOTP aware
     application to determine whether another IOTP application running
     elsewhere is working or not.

  These IOTP Transactions are "Baseline" transactions since they have
  been identified as a minimum useful set of transactions. Later
  versions of IOTP may include additional types of transactions.

  Each of the IOTP Transactions above involve:

  o  a number of organisations playing a Trading Role, and

  o  a set of Trading Exchanges. Each Trading Exchange involves the
     exchange of data, between Trading Roles, in the form of a set of
     Trading Components.

  Trading Roles, Trading Exchanges and Trading Components are described
  below.

































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2.1 Trading Roles

  The Trading Roles identify the different parts which organisations
  can take in a trade. The five Trading Roles used within IOTP are
  illustrated in the diagram below.

  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

             Merchant Customer Care Provider resolves   ----------
        ---------------------------------------------->| Merchant |
       |          Consumer disputes and problems       |Cust.Care.|
       |                                               | Provider |
       |                                                ----------
       |
                  Payment Handler accepts or makes     ----------
       |    ------------------------------------------>| Payment  |
       |   |             Payment for Merchant          | Handler  |
       |   |                                            ----------
       v   v
   ----------    Consumer makes purchases or obtains    ----------
  | Consumer |<--------------------------------------->| Merchant |
   ----------             refund from Merchant          ----------
       ^
       |         Delivery Handler supplies goods or     ----------
       |---------------------------------------------->|Deliverer |
                      services for Merchant            | Handler  |
                                                        ----------

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                   Figure 1 IOTP Trading Roles




















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  The roles are:

  o  Consumer. The person or organisation which is to receive and pay
     for the goods or services

  o  Merchant. The person or organisation from whom the purchase is
     being made and who is legally responsible for providing the goods
     or services and receives the benefit of the payment made

  o  Payment Handler. The entity that physically receives the payment
     from the Consumer on behalf of the Merchant

  o  Delivery Handler. The entity that physically delivers the goods or
     services to the Consumer on behalf of the Merchant.

  o  Merchant Customer Care Provider. The entity that is involved with
     customer dispute negotiation and resolution on behalf of the
     Merchant

  Roles may be carried out by the same organisation or different
  organisations. For example:

  o  in the simplest case one physical organisation (e.g., a merchant)
     could handle the purchase, accept the payment, deliver the goods
     and provide merchant customer care

  o  at the other extreme, a merchant could handle the purchase but
     instruct the consumer to pay a bank or financial institution,
     request that delivery be made by an overnight courier firm and to
     contact an organisation which provides 24x7 service if problems
     arise.

  Note that in this specification, unless stated to the contrary, when
  the words Consumer, Merchant, Payment Handler, Delivery Handler or
  Customer Care Provider are used, they refer to the Trading Role
  rather than an actual organisation.

  An individual organisation may take multiple roles. For example a
  company which is selling goods and services on the Internet could
  take the role of Merchant when selling goods or services and the role
  of Consumer when the company is buying goods or services itself.

  As roles occur in different places there is a need for the
  organisations involved in the trade to exchange data, i.e. to carry
  out Trading Exchanges, so that the trade can be completed.






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2.2 Trading Exchanges

  The Internet Open Trading Protocols identify four Trading Exchanges
  which involve the exchange of data between the Trading Roles. The
  Trading Exchanges are:

  o  Offer. The Offer Exchange results in the Merchant providing the
     Consumer with the reason why the trade is taking place. It is
     called an Offer since the Consumer must accept the Offer if a
     trade is to continue

  o  Payment. The Payment Exchange results in a payment of some kind
     between the Consumer and the Payment Handler. This may occur in
     either direction

  o  Delivery. The Delivery Exchange transmits either the on-line
     goods, or delivery information about physical goods from the
     Delivery Handler to the Consumer, and

  o  Authentication. The Authentication Exchange can be used by any
     Trading Role to authenticate another Trading Role to check that
     they are who they appear to be.

  IOTP Transactions are composed of various combinations of these
  Trading Exchanges.  For example, an IOTP Purchase transaction
  includes Offer, Payment, and Delivery Trading Exchanges.  As another
  example, an IOTP Value Exchange transaction is composed of an Offer
  Trading Exchange and two Payment Trading Exchanges.

  Trading Exchanges consist of Trading Components that are transmitted
  between the various Trading Roles.  Where possible, the number of
  round-trip delays in an IOTP Transaction is minimised by packing the
  Components from several Trading Exchanges into combination IOTP
  Messages.  For example, the IOTP Purchase transaction combines a
  Delivery Organisation Component with an Offer Response Component in
  order to avoid an extra Consumer request and response.

  Each of the IOTP Trading Exchanges is described in more detail below.
  For clarity of description, these describe the Trading Exchanges as
  though they were standalone operations.  For performance reasons, the
  Trading Exchanges are intermingled in the actual IOTP Transaction
  definitions.









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2.2.1 Offer Exchange

  The goal of the Offer Exchange is for the Merchant to provide the
  Consumer with information about the trade so that the Consumer can
  decide whether to continue with the trade. This is illustrated in the
  figure below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
  Consumer
    |  Merchant
STEP |     |
1.          Consumer decides to trade and sends information about the
            transaction (requests an offer) to the Merchant e.g.,
            using HTML.

    C --> M Data: Information on what is being purchased (Offer Request)
            - outside scope of IOTP

2.          Merchant checks the information provided by the Consumer,
            creates an Offer optionally signs it and sends it to the
            Consumer.

    C <-- M OFFER RESPONSE. Components: Status; Organisation(s)
            (Consumer, DelivTo, Merchant, Payment Handler, Customer
            Care); Order; Payment; Delivery; TradingRoleData (optional)
            Offer Response Signature (optional) that signs other
            components

3.          Consumer checks the information from the Merchant and
            decides whether to continue.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                          Figure 2 Offer Exchange

  An Offer Exchange uses the following Trading Components that are
  passed between the Consumer and the Merchant:

  o  the Status component is used to indicate to other parties that a
     valid Offer Response has been generated

  o  the Organisation Component contains information which describes
     the Organisations which are taking a role in the trade:

     -  the consumer provides information, about who the consumer is
        and, if goods or services are being delivered, where the goods
        or services are to be delivered to




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     -  the merchant augments this information by providing information
        about the merchant, the Payment Handler, the customer care
        provider and, if goods or services are being delivered, the
        Delivery Handler

  o  the Order Component contains descriptions of the goods or services
     which will result from the trade if the consumer agrees to the
     offer.  This information is sent by the Merchant to the consumer
     who should verify it

  o  the Payment Component generated by the Merchant, contains details
     of how much to pay, the currency and the payment direction, for
     example the consumer could be asking for a refund. Note that there
     may be more than one payment in a trade

  o  the Delivery Component, also generated by the Merchant, is used if
     goods or services are being delivered. This contains information
     about how delivery will occur, for example by post or using e-mail

  o  the Trading Role Data component contains data the Merchant wants
     to forward to another Trading Role such as a Payment Handler or
     Delivery Handler

  o  the "Offer Response" Signature Component, if present, digitally
     signs all of the above components to ensure their integrity.

  The exact content of the information provided by the Merchant to the
  Consumer will vary depending on the type of IOTP Transaction. For
  example:

  o  low value purchases may not need a signature

  o  the amount to be paid may vary depending on the payment brand and
     payment protocol used

  o  some offers may not involve the delivery of any goods

  o  a value exchange will involve two payments

  o  a merchant may not offer customer care.

  Information provided by the consumer to the merchant is provided
  using a variety of methods, for example, it could be provided:

  o  using [HTML] pages as part of the "shopping experience" of the
     consumer.





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  o  Using the Open Profiling Standard [OPS] which has recently been
     proposed,

  o  in the form of Organisation Components associated with an
     authentication of a Consumer by a Merchant

  o  as Order Components in a later version of IOTP.

2.2.2 Payment Exchange

  The goal of the Payment Exchange is for a payment to be made from the
  Consumer to a Payment Handler or vice versa using a payment brand and
  payment protocol selected by the Consumer. A secondary goal is to
  optionally provide the Consumer with a digitally signed Payment
  Receipt which can be used to link the payment to the reason for the
  payment as described in the Offer Exchange.

  Payment Exchanges can work in a variety of ways. The most general
  case where the trade is dependent on the payment brand and protocol
  used is illustrated in the diagram below. Simpler payment exchanges
  are possible.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 Consumer  Pay Handler
    |  Merchant |
STEP |     |     |
1.                 Consumer decides to trade and sends information
                   about the transaction (requests an offer) to the
                   Merchant e.g., using HTML.

    C --> M        Information on what is being paid for (outside
                   scope of IOTP

2.                 Merchant decides which payment brand, payment
                   protocols and currencies/amounts to offer,
                   places then in a Brand List Component and sends
                   them to the Consumer

    C <-- M        Components: Brand List

3.                 Consumer selects the payment brand, protocol and
                   currency/amount to use, creates a Brand Selection
                   component and sends it to the Merchant

    C --> M        Component: Brand List Selection






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4.                 Merchant checks Brand Selection, creates a Payment
                   Amount information, optionally signs it to
                   authorise payment and sends it to the Consumer

    C <-- M        Component: Payment; Organisation(s) (Merchant and
                   Payment Handler); Optional Offer Response Signature
                   that signs other components

5.                 Consumer checks the Payment Amount information and
                   if OK requests that the payment starts by sending
                   information to the Payment Handler

    C --------> P  PAYMENT REQUEST. Components: Status, Payment;
                   Organisations (Merchant and Payment Handler);
                   Trading Role Data (optional); Optional Offer
                   Response Signature that signs other components;
                   Pay Scheme Data

6.                 Payment Handler checks information including
                   optional signature and if OK starts exchanging Pay
                   Scheme Data components for selected payment brand
                   and payment protocol

    C <-------> P  PAYMENT EXCHANGE. Component: Pay Scheme Data

7.                 Eventually payment protocol messages finish so
                   Payment Handler sends Pay Receipt and optional
                   signature to the Consumer as proof of payment

    C <-------> P  PAYMENT RESPONSE. Components: Status, Pay Receipt;
                   Payment Note; Trading Role Data (optional);
                   Optional Offer Response Signature; Optional
                   Payment Receipt Signature that binds the payment
                   to the Offer

8.                 Consumer checks Payment Receipt is OK

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                         Figure 3 Payment Exchange

  A Payment Exchange uses the following Trading Components that are
  passed between the Consumer, the Merchant and the Payment Handler:

  o  The Brand List Component contains a list of payment brands (for
     example, MasterCard, Visa, Mondex, GeldKarte), payment protocols
     (for example SET Version 1.0, Secure Channel Credit Debit (SCCD -
     the name used for a credit or debit card payment where



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     unauthorised access to account information is prevented through
     use of secure channel transport mechanisms such as SSL/TLS) as
     well as currencies/amounts that apply. The Merchant sends the
     Brand List to the Consumer. The consumer compares the payment
     brands, protocols and currencies/amounts on offer with those that
     the Consumer supports and makes a selection.

  o  The Brand Selection Component contains the Consumer's selection.
     Payment brand, protocol, currency/amount and possibly protocol-
     specific information is sent back to the Merchant. This
     information may be used to change information in the Offer
     Exchange. For example, a merchant could choose to offer a discount
     to encourage the use of a store card.

  o  the Status component is used to indicate to the Payment Handler
     that an earlier exchange (e.g., an Offer Exchange) has
     successfully completed and by the Payment Handler to indicate the
     completion status of the Payment Exchange.

  o  The Organisation Components are generated by the Merchant. They
     contain details of the Merchant and Payment Handler Roles:

     -  the Merchant role is required so that the Payment Handler can
        identify which Merchant initiated the payment. Typically, the
        result of the Payment Handler accepting (or making) a payment
        on behalf of the Merchant will be a credit or debit transaction
        to the Merchant's account held by the Payment Handler. These
        transactions are outside the scope of this version of IOTP

     -  the Payment Handler role is required so that the Payment
        Handler can check that it is the correct Payment Handler to be
        used for the payment

  o  The Payment Component contains details of how much to pay, the
     currency and the payment direction

  o  The "Offer Response" Signature Component, if present, digitally
     signs all of the above components to ensure their integrity. Note
     that the Brand List and Brand Selection Components are not signed
     until the payment information is created (step 4 in the diagram)

  o  the Trading Role Data component contains from other roles (e.g., a
     Merchant) that needs to be  forwarded to the Payment Handler

  o  The Payment Scheme Component contains messages from the payment
     protocol used in the Trade. For example they could be SET
     messages, Mondex messages, GeldKarte Messages or one of the other
     payment methods supported by IOTP. The content of the Payment



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     Scheme Component is defined in the supplements that describe how
     IOTP works with various payment protocols.

  o  The Payment Receipt Component contains a record of the payment.
     The content depends upon the payment protocol used.

  o  The "Payment Receipt" Signature Component provides proof of
     payment by digitally signing both the Payment Receipt Component
     and the Offer Response Signature. The signature on the offer
     digitally signs the Order, Organisation and Delivery Components
     contained in the Offer.  This signature effectively binds the
     payment to the offer.

  The example of a Payment Exchange above is the most general case.
  Simpler cases are also possible. For example, if the amount paid is
  not dependent on the payment brand and protocol selected then the
  payment information generated by step 3 can be sent to the Consumer
  at the same time as the Brand List Component generated by step 1.
  These and other variations are described in the Baseline Purchase
  IOTP Transaction (see section 9.1.8).

2.2.3 Delivery Exchange

  The goal of the Delivery Exchange is to cause purchased goods to be
  delivered to the consumer either online or via physical delivery. A
  second goal is to provide a "delivery note" to the consumer,
  providing details about the delivery, such as shipping tracking
  number. The result of the delivery may also be signed so that it can
  be used for customer care in the case of problems with physical
  delivery. The message flow is illustrated in the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
 CONSUMER  DELIVERY
    |        HANDLER
    |  Merchant |
STEP |     |     |
1.                 Consumer decides to trade and sends information
                   about what to deliver and who is to take delivery,
                   to the Merchant e.g., using HTML.

    C --> M        Information on what is being delivered (outside
                   scope of IOTP)

2.                 Merchant checks the information provided by the
                   Consumer, adds information about how the delivery
                   will occur, information about the Organisations
                   involved in the delivery and optionally sings it
                   and sends it to the Consumer



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    C <-- M        Components: Delivery; Organisations (Delivery
                   Handler, Deliver To); Order, Optional Offer
                   Response Signature

3.                 Consumer checks delivery information is OK,
                   obtains authorisation for the delivery, for
                   example by making a payment, and sends the
                   delivery information to the Delivery Handler

    C --------> D  DELIVERY REQUEST. Components: Status; Delivery,
                   Organisations: (Merchant, Delivery Handler,
                   DelivTo); Order, Trading Role Data (optional);
                   Optional Offer Response Signature, Optional
                   Payment Receipt Signature (from Payment Exchange)

4.                 Delivery Handler checks information and
                   authorisation. Starts or schedules delivery and
                   creates and then sends a delivery not tot the
                   Consumer which can optionally be signed.

    C <-------- D  DELIVERY RESPONSE. Components: Status; Delivery
                   Note, Trading Role Data (optional); Optional
                   Delivery Response Signature

5.                 Consumer checks delivery note is OK and accepts or
                   waits for delivery as described in the the Delivery
                   Note.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                        Figure 4 Delivery Exchange

A Delivery Exchange uses the following Trading Components that are
passed between the Consumer, the Merchant and the Delivery Handler:

  o  the Status component is used to indicate to the Delivery Handler
     that an earlier exchange (e.g., an Offer Exchange or Payment
     Exchange) has successfully completed and by the Delivery Handler
     to indicate the completion status of the Delivery Exchange.

  o  The Organisation Component(s) contain details of the Deliver To,
     Delivery Handler and Merchant Roles:

     -  the Deliver To role indicates where the goods or services are
        to be delivered to






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     -  the Delivery Handler role is required so that the Delivery
        Handler can check that she is the correct Delivery Handler to
        do the delivery

     -  the Merchant role is required so that the Delivery Handler can
        identify which Merchant initiated the delivery

  o  The Order Component, contains information about the goods or
     services to be delivered

  o  The Delivery Component contains information about how delivery
     will occur, for example by post or using e-mail.

  o  The "Offer Response" Signature Component, if present, digitally
     signs all of the above components to ensure their integrity.

  o  The "Payment Receipt" Signature Component provides proof of
     payment by digitally signing the Payment Receipt Component and the
     Offer Signature. This is used by the Delivery Handler to check
     that delivery is authorised

  o  The Delivery Note Component contains customer care information
     related to a physical delivery, or alternatively the actual
     "electronic goods".  The Consumer's software does not interpret
     information about a physical delivery but should have the ability
     to display the information, both at the time of the delivery and
     later if the Consumer selects the Trade to which this delivery
     relates from a transaction list

  o  The "Delivery Response" Signature Component, if present, provides
     proof of the results of the Delivery by digitally signing the
     Delivery Note and any Offer Response or Payment Response
     signatures that the Delivery Handler received.

2.2.4 Authentication Exchange

  The goal of the Authentication Exchange is to allow one Organisation,
  for example a financial institution, to be able to check that another
  Organisation, for example a consumer, is who they appear to be.

  An Authentication Exchange involves:

  o  an Authenticator - the Organisation which is requesting the
     authentication, and

  o  an Authenticatee - the Organisation being authenticated.





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  This is illustrated in the diagram below.

+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
Organisation 1
(Authenticatee)
    |   Organisation 2
    |  (Authenticator)
STEP |     |
1.          First Organisation, e.g., a Consumer, takes an action (for
            example by pressing a button on an HTML page) which
            requires that the Organisation is authenticated

    1 --> 2 Need for Authentication (outside scope of IOTP)

2.          The second Organisation generates an Authentication
            Request - including challenge data, and a list of the
            algorithms that may be used for the authentication -
            and/or a request for the Organisation information then
            sends it to the first Organisation

    1 <-- 2 AUTHENTICATION REQUEST. Components: Authentication
            Request, Trading Role Information Request

3.          The first Organisation optionally checks any signature
            associated with the Authentication Request then uses the
            specified authentication algorithm to generate an
            Authentication Response which is sent back to the second
            Organisation together with details of any Organisation
            information requested

    1 --> 2 AUTHENTICATION RESPONSE. Component: Authentication
            Response, Organisation(s)

4.          The Authentication Response is checked against the
            challenge data to check that the first Organisation is
            who they appear to be and the result recorded in a Status
            Component which is then sent back to the first
            Organisation.

    1 <-- 2 AUTHENTICATION STATUS. Component: Status

5.          The first Organisation then optionally checks the results
            indicated by the Status and any associated signature and
            takes the appropriate action or stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                     Figure 5 Authentication Exchange



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  An Authentication Exchange uses the following Trading Components that
  are passed between the two Organisations:

  o  the Authentication Request Component that requests an
     Authentication and indicates the authentication algorithm and
     optional challenge data to be used.

  o  A Trading Role Information Request Component that requests
     information about an Organisation, for example a ship to address.

  o  The Authentication Response Component which contains the challenge
     response generated by the recipient of the Authentication Request
     Component.

  o  Organisation Components that contain the result of the Trading
     Role Information Request

  o  the Status Component which contains the results of the second
     party's verification of the Authentication Response.

2.3 Scope of Baseline IOTP

  This specification describes the IOTP Transactions which make up
  Baseline IOTP. As described in the preface, IOTP will evolve over
  time. This section defines the initial conformance criteria for
  implementations that claim to "support IOTP."

  The main determinant on the scope of an IOTP implementation is the
  roles which the solution is designed to support. The roles within
  IOTP are described in more detail in section 2.1 Trading Roles. To
  summarise the roles are: Merchant, Consumer, Payment Handler,
  Delivery Handler and Customer Care Provider.

  Payment Handlers who can be of three types:

  o  those who accept a payment as part of a purchase or make a payment
     as part of a refund,

  o  those who accept value as part of a deposit transaction, or

  o  those that issue value a withdrawal transaction

  The following table defines, for each role, the IOTP Transactions and
  Trading Blocks which must be supported for that role.







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                      Merchants

                       ECash    ECash
               Store   Value    Value    Consumer  Payment   Delivery
                       Issuer Acquirer             Handler   Handler

TRANSACTIONS

Purchase        Must                        Must

                      Merchants

                       ECash    ECash
               Store   Value    Value    Consumer  Payment   Delivery
                       Issuer Acquirer             Handler   Handler

Refund          Must                         b)
                                         Depends

Authentication   May     Must     May        b)
                                         Depends

Value Exchange   May                        Must

Withdrawal               Must                b)
                                         Depends

Deposit                          Must        b)
                                         Depends

Inquiry         Must     Must    Must       May       Must      Must

Ping            Must     Must    Must       May       Must      Must

TRADING BLOCKS

TPO             Must     Must    Must       Must

TPO Selection   Must     Must    Must       Must

Auth-Request     a)               a)         a)
              Depends          Depends   Depends

Auth-Reply       a)               a)         a)
              Depends          Depends   Depends

Offer Response  Must     Must    Must       Must




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Payment                                     Must      Must
Request

Payment                                     Must      Must
Exchange

Payment                                     Must      Must
Response

Delivery                                    Must                Must
Request

Delivery                                    Must                Must
Response

                      Merchants

                       ECash    ECash
               Store   Value    Value    Consumer  Payment   Delivery
                       Issuer Acquirer             Handler   Handler

Inquiry         Must     Must    Must       Must      Must      Must
Request

Inquiry         Must     Must    Must       Must      Must      Must
Response

Ping Request    Must     Must    Must       Must      Must      Must

Ping Response   Must     Must    Must       Must      Must      Must

Signature       Must     Must    Must     Limited     Must      Must

Error           Must     Must    Must       Must      Must      Must

  In the above table:

  o  "Must" means that a Trading Role must support the Transaction or
     Trading Block.

  o  "May" means that an implementation may support the Transaction or
     Trading Block at the option of the developer.

  o  "Depends" means implementation of the Transaction or Trading Block
     depends on one of the following conditions:

     -  if Baseline Authentication IOTP Transaction is supported;




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     -  if required by a Payment Method as defined in its IOTP
        Supplement document.

  o  "Limited" means the Trading Block must be understood and its
     content manipulated but not in every respect. Specifically, on the
     Signature Block, Consumers do not have to be able to validate
     digital signatures.

  An IOTP solution must support all the IOTP Transactions and Trading
  Blocks required by at least one role (column) as described in the
  above table for that solution to be described as "supporting IOTP".

3. Protocol Structure

  The previous section provided an introduction which explained:

  o  Trading Roles which are the different roles which Organisations
     can take in a trade: Consumer, Merchant, Payment Handler, Delivery
     Handler and Customer Care Provider, and

  o  Trading Exchanges where each Trading Exchange involves the
     exchange of data, between Trading Roles, in the form of a set of
     Trading Components.

  This section describes:

  o  how Trading Components are constructed into Trading Blocks and the
     IOTP Messages which are physically sent in the form of [XML]
     documents between the different Trading Roles,

  o  how IOTP Messages are exchanged between Trading Roles to create an
     IOTP Transaction

  o  the XML definitions of an IOTP Message including a Transaction
     Reference Block - an XML element which identifies an IOTP
     Transaction and the IOTP Message within it

  o  the definitions of the XML ID Attributes which are used to
     identify IOTP Messages, Trading Blocks and Trading Components and
     how these are referred to using Element References from other XML
     elements

  o  how extra XML Elements and new user defined values for existing
     IOTP codes can be used when Extending IOTP,

  o  how IOTP uses the Packaged Content Element to embed data such as
     payment protocol messages or detailed order definitions within an
     IOTP Message



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RFC 2801                       IOTP/1.0                       April 2000


  o  how IOTP Identifies Languages so that different languages can be
     used within IOTP Messages

  o  how IOTP handles both Secure and Insecure Net Locations when
     sending messages

  o  how an IOTP Transaction can be cancelled.

3.1 Overview

3.1.1 IOTP Message Structure

  The structure of an IOTP Message and its relationship with Trading
  Blocks and Trading Components is illustrated in the diagram below.





































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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

IOTP MESSAGE  <---------- IOTP Message - an XML Document which is
|                        transported between the Trading Roles
|-Trans Ref Block <----- Trans Ref Block - contains information which
|  |                     describes the IOTP Transaction and the IOTP
|  |                     Message.
|  |-Trans Id Comp. <--- Transaction Id Component - uniquely
|  |                     identifies the IOTP Transaction. The Trans Id
|  |                     Components are the same across all IOTP
|  |                     messages that comprise a single IOTP
|  |                     transaction.
|  |-Msg Id Comp. <----- Message Id Component - identifies and
|                        describes an IOTP Message within an IOTP
|                        Transaction
|-Signature Block <----- Signature Block (optional) - contains one or
|  |                     more Signature Components and their
|  |                     associated Certificates
|  |-Signature Comp. <-- Signature Component - contains digital
|  |                     signatures. Signatures may sign digests of
|  |                     the Trans Ref Block and any Trading Component
|  |                     in any IOTP Message in the same IOTP
|  |                     transaction.
|  |-Certificate Comp. < Certificate Component (Optional) Used to check
|                        the signature.
|-Trading Block <------- Trading Block - an XML Element within an IOTP
|  |-Trading Comp.       Message that contains a predefined set of
|  |-Trading Comp.      Trading Components
|  |-Trading Comp.
|  |-Trading Comp. <--- Trading Components - XML Elements within a
|                        Trading Block that contain a predefined set
|-Trading Block          of XML elements and attributes containing
|  |-Trading Comp.       information required to support a Trading
|  |-Trading Comp.       Exchange
|  |-Trading Comp.
|  |-Trading Comp.
|  |-Trading Comp.

*-*-*-*-*-*--*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                     Figure 6 IOTP Message Structure

  The diagram also introduces the concept of a Transaction Reference
  Block.  This block contains, amongst other things, a globally unique
  identifier for the IOTP Transaction. Also each block and component is
  given an ID Attribute (see section 3.4) which is unique within an
  IOTP Transaction.  Therefore the combination of the ID attribute and




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RFC 2801                       IOTP/1.0                       April 2000


  the globally unique identifier in the Transaction Reference Block is
  sufficient to uniquely identify any Trading Block or Trading
  Component.

3.1.2 IOTP Transactions

  A predefined set of IOTP Messages exchanged between the Trading Roles
  constitute an IOTP Transaction. This is illustrated in the diagram
  below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*


    CONSUMER                                              MERCHANT
                                                      Generate first
                                                       IOTP Message
                                  ---                        |
                                 |   |                       v
Process incoming                 | I |                 -------------
 IOTP Message &   <------------- |   | ------------ | IOTP Message |
generate next IOTP                |   |                 -------------
    Message                      | N |
       |                         |   |
       v                         |   |
 -------------                   | T |              Process incoming
| IOTP Message |  -------------- |   | ----------->  IOTP Message &
 -------------                   |   |                 generate next
                                 | E |                  IOTP Message
                                 |   |                       |
                                 |   |                       v
Process incoming                 | R |                 -------------
  IOTP Message    <------------- |   | ------------ | IOTP Message |
generate last IOTP                |   |                 -------------
 Message & stop                  | N |
       |                         |   |
       v                         |   |
 -------------                   | E |                  Process last
| IOTP Message |  -------------- |   | ------------->  incoming IOTP
 -------------                   |   |                Message & stop
       |                         | T |                       |
       v                         |   |                       v
      STOP                        ---                       STOP

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-

                      Figure 7 An IOTP Transaction





Burdett                      Informational                     [Page 34]

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  In the above diagram the Internet is shown as the transport
  mechanism.  This is not necessarily the case. IOTP Messages can be
  transported using a variety of transport mechanisms.

  The IOTP Transactions (see section 9) in this version of IOTP are
  specifically:

  o  Purchase. This supports a purchase involving an offer, a payment
     and optionally a delivery

  o  Refund. This supports the refund of a payment as a result of,
     typically, an earlier purchase

  o  Value Exchange. This involves two payments which result in the
     exchange of value from one combination of currency and payment
     method to another

  o  Authentication. This supports the remote authentication of one
     Trading Role by another Trading Role using a variety of
     authentication algorithms, and the provision of an Organisation
     Information about the Trading Role that is being authenticated for
     use in, for example, the creation of an offer

  o  Withdrawal. This supports the withdrawal of electronic cash from a
     financial institution

  o  Deposit. This supports the deposit of electronic cash at a
     financial institution

  o  Inquiry This supports inquiries on the status of an IOTP
     transaction which is either in progress or is complete

  o  Ping This supports a simple query which enables one IOTP aware
     application to determine whether another IOTP application running
     elsewhere is working or not.

3.2 IOTP Message

  As described earlier, IOTP Messages are [XML] documents which are
  physically sent between the different Trading Roles that are taking
  part in a trade.

  The XML definition of an IOTP Message is as follows.

  <!ELEMENT IotpMessage
     ( TransRefBlk,
       SigBlk?,
       ErrorBlk?,



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RFC 2801                       IOTP/1.0                       April 2000


       ( AuthReqBlk |
         AuthRespBlk |
         AuthStatusBlk |
         CancelBlk |
         DeliveryReqBlk |
         DeliveryRespBlk |
         InquiryReqBlk |
         InquiryRespBlk |
         OfferRespBlk |
         PayExchBlk |
         PayReqBlk |
         PayRespBlk |
         PingReqBlk |
         PingRespBlk |
         TpoBlk |
         TpoSelectionBlk
       )*
     ) >
  <!ATTLIST IotpMessage
    xmlns                     CDATA
    'iotp:ietf.org/iotp-v1.0'

  Content:

  TransRefBlk        This contains information which describes an IOTP
                     Message within an IOTP Transaction (see section
                     3.3 immediately below)

  AuthReqBlk,        These are the Trading Blocks.
  AuthRespBlk,
  DeliveryReqBlk,    The Trading Blocks present within an IOTP Message,
  DeliveryRespBlk    and the content of a Trading Block itself is
  ErrorBlk           dependent on the type of IOTP Transaction being
  InquiryReqBlk,     carried out - see the definition of each
  InquiryRespBlk,    transaction in section 9 Internet Open Trading
  OfferRespBlk,      Protocol Transactions.
  PayExchBlk,
  PayReqBlk,         Full definitions of each Trading Block are
  PayRespBlk,        described in section 8.
  PingReqBlk,
  PingRespBlk,
  SigBlk,
  TpoBlk,
  TpoSelectionBlk

  Attributes:

  xmlns              The [XML Namespace] definition for IOTP messages.



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RFC 2801                       IOTP/1.0                       April 2000


3.2.1 XML Document Prolog

  The IOTP Message is the root element of the XML document. It
  therefore needs to be preceded by an appropriate XML Document Prolog.
  For example:

  <?XML Version='1.0'?>
  <!DOCTYPE IotpMessage >
  <IotpMessage>
   ...
  </IotpMessage>

3.3 Transaction Reference Block

  A Transaction Reference Block contains information which identifies
  the IOTP Transaction and IOTP Message. The Transaction Reference
  Block contains:

  o  a Transaction Id Component which globally uniquely identifies the
     IOTP Transaction. The Transaction Id Components are the same
     across all IOTP messages that comprise a single IOTP transaction,

  o  a Message Id Component which provides control information about
     the IOTP Message as well as uniquely identifying the IOTP Message
     within an IOTP Transaction, and

  o  zero or more Related To Components which link this IOTP
     Transaction to either other IOTP Transactions or other events
     using the identifiers of those events.

  The definition of a Transaction Reference Block is as follows:

  <!ELEMENT TransRefBlk (TransId, MsgId, RelatedTo*) >
  <!ATTLIST TransRefBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Transaction Reference Block within the IOTP
                     Transaction (see section 3.4 ID Attributes).

  Content:

  TransId            See 3.3.1 Transaction Id Component immediately
                     below.

  MsgId              See 3.3.2 Message Id Component immediately below.



Burdett                      Informational                     [Page 37]

RFC 2801                       IOTP/1.0                       April 2000


  RelatedTo          See 3.3.3 Related To Component immediately below.

3.3.1 Transaction Id Component

  This contains information which globally uniquely identifies the IOTP
  Transaction. Its definition is as follows:

  <!ELEMENT TransId EMPTY >
  <!ATTLIST TransId
   ID                 ID      #REQUIRED
   Version            NMTOKEN #FIXED '1.0'
   IotpTransId        CDATA   #REQUIRED
   IotpTransType      CDATA   #REQUIRED
   TransTimeStamp     CDATA   #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Transaction Id Component within the IOTP
                     Transaction.

  Version            This identifies the version of IOTP, and therefore
                     the structure of the IOTP Messages, which the IOTP
                     Transaction is using.

  IotpTransId        Contains data which uniquely identifies the IOTP
                     Transaction. It must conform to the rules for
                     Message Ids in [RFC 822].

  IotpTransTyp       This is the type of IOTP Transaction being carried
                     out. For Baseline IOTP it identifies a "standard"
                     IOTP Transaction and implies the sequence and
                     content of the IOTP Messages exchanged between the
                     Trading Roles. The valid values for Baseline IOTP
                     are:
                      o BaselineAuthentication
                      o BaselineDeposit
                      o BaselinePurchase
                      o BaselineRefund
                      o BaselineWithdrawal
                      o BaselineValueExchange
                      o BaselineInquiry
                      o BaselinePing

                     Values of IotpTransType are managed under the
                     procedure described in section 12 IANA
                     Considerations which also allows user defined
                     values of IotpTransType to be defined.



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RFC 2801                       IOTP/1.0                       April 2000


                     In later versions of IOTP, this list will be
                     extended to support different types of standard
                     IOTP Transaction. It is also likely to support the
                     type Dynamic which indicates that the sequence of
                     steps within the transaction are non-standard.

  TransTimeStamp     Where the system initiating the IOTP Transaction
                     has an internal clock, it is set to the time at
                     which the IOTP Transaction started in [UTC]
                     format.

                     The main purpose of this attribute is to provide
                     an alternative way of identifying a transaction by
                     specifying the time at which it started.

                     Some systems, for example, hand held devices may
                     not be able to generate a  time stamp. In this
                     case this attribute should contain the value "NA"
                     for Not Available.

3.3.2 Message Id Component

  The Message Id Component provides control information about the IOTP
  Message as well as uniquely identifying the IOTP Message within an
  IOTP Transaction. Its definition is as follows.

  <!ELEMENT MsgId EMPTY >
  <!ATTLIST MsgId
   ID                 ID      #REQUIRED
   RespIotpMsg        NMTOKEN #IMPLIED
   xml:lang           NMTOKEN #REQUIRED
   LangPrefList       NMTOKENS #IMPLIED
   CharSetPrefList    NMTOKENS #IMPLIED
   SenderTradingRoleRef NMTOKEN #IMPLIED
   SoftwareId         CDATA   #REQUIRED
   TimeStamp          CDATA   #IMPLIED >

  Attributes:

  ID                     An identifier which uniquely identifies the
                         IOTP Message within the IOTP Transaction (see
                         section 3.4 ID Attributes). Note that if an
                         IOTP Message is resent then the value of this
                         attribute remains the same.

  RespIotpMsg            This contains the ID attribute of the Message
                         Id Component of the IOTP Message to which this
                         IOTP Message is a response. In this way all



Burdett                      Informational                     [Page 39]

RFC 2801                       IOTP/1.0                       April 2000


                         the IOTP Messages in an IOTP Transaction are
                         unambiguously linked together. This field is
                         required on every IOTP Message except the
                         first IOTP Message in an IOTP Transaction.

  SenderTradingRoleRef   The Element Reference (see section 3.5) of the
                         Trading Role which has generated the IOTP
                         message. It is used to identify the Net
                         Locations (see section 3.9) of the Trading
                         Role to which problems Technical Errors (see
                         section 4.1) with any of Trading Blocks should
                         be reported.

  Xml:lang               Defines the language used by attributes or
                         child elements within this component, unless
                         overridden by an xml:lang attribute on a child
                         element. See section 3.8 Identifying
                         Languages.

  LangPrefList           Optional list of Language codes that conform
                         to [XML] Language Identification. It is used
                         by the sender to indicate, in preference
                         sequence, the languages that the receiver of
                         the message ideally should use when generating
                         a response. There is no obligation on the
                         receiver to respond using one of the indicated
                         languages, but using one of the languages is
                         likely to provide an improved user experience.

  CharSetPrefList        Optional list of Character Set identifiers
                         that conform to [XML] Characters. It is used
                         by the sender to indicate, in preference
                         sequence, the character sets that the receiver
                         of the message ideally should use when
                         generating a response. There is no obligation
                         on the receiver to respond using one of the
                         character sets indicated, but using one of the
                         character sets is likely to provide an
                         improved user experience.

  SoftwareId             This contains information which identifies the
                         software which generated the IOTP Message. Its
                         purpose is to help resolve interoperability
                         problems that might occur as a result of
                         incompatibilities between messages produced by
                         different software. It is a single text string
                         in the language defined by xml:lang. It must
                         contain, as a minimum:



Burdett                      Informational                     [Page 40]

RFC 2801                       IOTP/1.0                       April 2000


                         o the name of the software manufacturer
                         o the name of the software
                         o the version of the software, and
                         o the build of the software

  TimeStamp              Where the device sending the message has an
                         internal clock, it is set to the time at which
                         the IOTP Message was created in [UTC] format.

3.3.3 Related To Component

  The Related To Component links IOTP Transactions to either other IOTP
  Transactions or other events using the identifiers of those events.
  Its definition is as follows.

  <!ELEMENT RelatedTo (PackagedContent) >
  <!ATTLIST RelatedTo
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   RelationshipType   NMTOKEN #REQUIRED
   Relation           CDATA   #REQUIRED
   RelnKeyWords       NMTOKENS #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Related To Component within the IOTP Transaction.

  xml:lang           Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.

  RelationshipType   Defines the type of the relationship. Valid values
                     are:

                      o IotpTransaction. in which case the Packaged
                        Content Element contains an IotpTransId of
                        another IOTP Transaction
                      o Reference in which case the Packaged Content
                        Element contains the reference of some other,
                        non-IOTP document.

                     Values of RelationshipType are controlled under
                     the procedures defined in section 12 IANA
                     Considerations which also allows user defined
                     values to be defined.




Burdett                      Informational                     [Page 41]

RFC 2801                       IOTP/1.0                       April 2000


  Relation           The Relation attribute contains a phrase in the
                     language defined by xml:lang which describes the
                     nature of the relationship between the IOTP
                     transaction that contains this component and
                     another IOTP Transaction or other event. The exact
                     words to be used are left to the implementers of
                     the IOTP software.

                     The purpose of the attribute is to provide the
                     Trading Roles involved in an IOTP Transaction with
                     an explanation of the nature of the relationship
                     between the transactions.

                     Care should be taken that the words used to in the
                     Relation attribute indicate the "direction" of the
                     relationship correctly. For example: one
                     transaction might be a refund for another earlier
                     transaction. In this case the transaction which is
                     a refund should contain in the Relation attribute
                     words such as "refund for" rather than "refund to"
                     or just "refund".

  RelnKeyWords       This attribute contains keywords which could be
                     used to help identify similar relationships, for
                     example all refunds. It is anticipated that
                     recommended keywords will be developed through
                     examination of actual usage. In this version of
                     the specification there are no specific
                     recommendations and the keywords used are at the
                     discretion of implementers.

  Content:

  PackagedContent    The Packaged Content (see section 3.7) contains
                     data which identifies the related transaction. Its
                     format varies depending on the value of the
                     RelationshipType.

3.4 ID Attributes

  IOTP Messages, Blocks (i.e. Transaction Reference Blocks and Trading
  Blocks), Trading Components (including the Transaction Id Component
  and the Signature Component) and some of their child elements are
  each given an XML "ID" attribute which is used to identify an
  instance of these XML elements. These identifiers are used so that
  one element can be referenced by another. All these attributes are
  given the attribute name ID.




Burdett                      Informational                     [Page 42]

RFC 2801                       IOTP/1.0                       April 2000


  The values of each ID attribute are unique within an IOTP transaction
  i.e. the set of IOTP Messages which have the same globally unique
  Transaction ID Component. Also, once the ID attribute of an element
  has been assigned a value it is never changed. This means that
  whenever an element is copied, the value of the ID attribute remains
  the same.

  As a result it is possible to use these IDs to refer to and locate
  the content of any IOTP Message, Block or Component from any other
  IOTP Message, Block or Component in the same IOTP Transaction using
  Element References (see section 3.5).

  This section defines the rules for setting the values for the ID
  attributes of IOTP Messages, Blocks and Components.

3.4.1 IOTP Message ID Attribute Definition

  The ID attribute of the Message Id Component of an IOTP Message must
  be unique within an IOTP Transaction. It's definition is as follows:

  IotpMsgId_value  ::= IotpMsgIdPrefix IotpMsgIdSuffix
  IotpMsgIdPrefix  ::= NameChar (NameChar)*
  IotpMsgIdSuffix  ::= Digit (Digit)*

  IotpMsgIdPrefix    Apart from messages which contain: an Inquiry
                     Request Trading Block, an Inquiry Response Trading
                     Block, a Ping Request Trading Block or a Ping
                     Response Trading Block; then the same prefix is
                     used for all messages sent by the Merchant or
                     Consumer role as follows:

                      o "M" - Merchant
                      o "C" - Consumer

                     For messages which contain an Inquiry Request
                     Trading Block or a Ping Request Trading Block, the
                     prefix is set to "I" for Inquiry.

                     For messages which contain an Inquiry Response
                     Trading Block or a Ping Response Trading Block,
                     the prefix is set to "Q".

                     The prefix for the other roles in a trade is
                     contained within the Organisation Component for
                     the role and are typically set by the Merchant.
                     The following is recommended as a guideline and
                     must not be relied upon:




Burdett                      Informational                     [Page 43]

RFC 2801                       IOTP/1.0                       April 2000


                      o "P" - First (only) Payment Handler
                      o "R" - Second Payment Handler
                      o "D" - Delivery Handler
                      o "C" - Deliver To

                     As a guideline, prefixes should be limited to one
                     character.

                     NameChar has the same definition as the [XML]
                     definition of NameChar.

  IotpMsgIdSuffix    The suffix consists of one or more digits. The
                     suffix must be unique within a Trading Role within
                     an IOTP Transaction. The following is recommended
                     as a guideline and must not be relied upon:

                      o the first IOTP Message sent by a trading role
                        is given the suffix "1"
                      o the second and subsequent IOTP Messages sent
                        by the same trading role are incremented by one
                        for each message
                      o no leading zeroes are included in the suffix

                     Put more simply the Message Id Component of the
                     first IOTP Message sent by a Consumer would have
                     an ID attribute of, "C1", the second "C2", the
                     third "C3" etc.

                     Digit has the same definition as the [XML]
                     definition of Digit.

3.4.2 Block and Component ID Attribute Definitions

  The ID Attribute of Blocks and Components must also be unique within
  an IOTP Transaction. Their definition is as follows:

  BlkOrCompId_value ::= IotpMsgId_value "." IdSuffix
  IdSuffix ::= Digit (Digit)*

  IotpMsgId_value    The ID attribute of the Message ID Component of
                     the IOTP Message where the Block or Component is
                     first used.

                     In IOTP, Trading Components and Trading Blocks are
                     copied from one IOTP Message to another. The ID
                     attribute does not change when an existing Trading
                     Block or Component is copied to another IOTP
                     Message.



Burdett                      Informational                     [Page 44]

RFC 2801                       IOTP/1.0                       April 2000


  IdSuffix           The suffix consists of one or more digits. The
                     suffix must be unique within the ID attribute of
                     the Message ID Component used to generate the ID
                     attribute. The following is recommended as a
                     guideline and must not be relied upon:

                      o the first Block or Component sent by a trading
                        role is given the suffix "1"
                      o the ID attributes of the second and subsequent
                        Blocks or Components are incremented by one for
                        each new Block or Component added to an IOTP
                        Message
                      o no leading zeroes are included in the suffix

                     Put more simply, the first new Block or Component
                     added to the second IOTP Message sent, for
                     example, by a consumer would have a an ID
                     attribute of "C2.1", the second "C2.2", the third
                     "C2.3" etc.

                     Digit has the same definition as the [XML]
                     definition of Digit.





























Burdett                      Informational                     [Page 45]

RFC 2801                       IOTP/1.0                       April 2000


3.4.3 Example of use of ID Attributes

  The diagram below illustrates how ID attribute values are used.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

     1st  IOTP MESSAGE                          2nd IOTP MESSAGE
   (e.g., from Merchant to                    (e.g., from Consumer to
          Consumer                              Payment Handler)

IOTP MESSAGE                               IOTP MESSAGE *
|-Trans Ref Block. ID=M1.1                 |-Trans Ref Block.ID=C1.1*
|  |-Trans Id Comp. ID = M1.2 ------------>|  |-Trans Id Comp.
|  |                         Copy Element  |  |  ID=M1.2
|  |-Msg Id Comp. ID = M1                  |  |-Msg Id Comp. ID=C1 *
|                                          |
|-Signature Block. ID=M1.8                 |-Signature Block.ID=C1.5*
|  |-Sig Comp. ID=M1.15 ------------------>|  |-Comp. ID=M1.15
|                            Copy Element  |
|-Trading Block. ID=M1.3                   |-Trading Block.ID=C1.2 *
|  |-Comp. ID=M1.4 -------------------------->|-Comp. ID=M1.4
|  |                         Copy Element     |
|  |-Comp. ID=M1.5 -------------------------->|-Comp. ID=M1.5
|  |                         Copy Element     |
|  |-Comp. ID=M1.6                            |-Comp. ID=C1.3 *
|  |-Comp. ID=M1.7                            |-Comp. ID=C1.4 *
|
|-Trading Block. ID=M1.9
   |-Comp. ID=M1.10                             * = new elements
   |-Comp. ID=M1.11
   |-Comp. ID=M1.12
   |-Comp. ID=M1.13

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-

                  Figure 8 Example use of ID attributes

3.5 Element References

  A Trading Component or one of its child XML elements, may contain an
  XML attribute that refers to another Block (i.e. a Transaction
  Reference Block or a Trading Block) or Trading Component (including a
  Transaction Id and Signature Component). These Element References are
  used for many purposes, a few examples include:

  o  identifying an XML element whose Digest is included in a Signature
     Component,




Burdett                      Informational                     [Page 46]

RFC 2801                       IOTP/1.0                       April 2000


  o  referring to the Payment Handler Organisation Component which is
     used when making a Payment

  An Element Reference always contains the value of an ID attribute of
  a Block or Component.

  Identifying the IOTP Message, Trading Block or Trading Component
  which is referred to by an Element Reference, involves finding the
  XML element which:

  o  belongs to the same IOTP Transaction (i.e. the Transaction Id
     Components of the IOTP Messages match), and

  o  where the value of the ID attribute of the element matches the
     value of the Element Reference.

  Note: The term "match" in this specification has the same definition
  as the [XML] definition of match.

  An example of "matching" an Element Reference is illustrated in the
  example below.






























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  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

        1st  IOTP MESSAGE                          2nd IOTP MESSAGE
      (e.g., from Merchant to                    (e.g., from Consumer to
             Consumer                              Payment Handler)

  IOTP MESSAGE                               IOTP MESSAGE
   |-Trans Ref Block. ID=M1.1     Trans ID    |-Trans RefBlock. ID=C1.1
   |  |-Trans Id Comp. ID = M1.2 <-Components-|->|-TransId Comp.ID=M1.2
   |  |                            must be    |  |
   |  |-Msg Id Comp. ID = M1      Identical   |  |-Msg Id Comp. ID=C1
   |                                  ^       |
   |-Signature Block. ID=M1.8         |       |-Signature Block.ID=C1.5
   |  |-Sig Comp. ID=M1.15            |       |  |-Comp. ID=M1.15
   |                                 AND      |
   |-Trading Block. ID=M1.3           |       |-Trading Block. ID=C1.2
   |  |-Comp. ID=M1.4                 |          |-Comp. ID=M1.4
   |  |                               v          |
   |  |-Comp. ID=M1.5 <-------- -ID Attribute    |-Comp. ID=M1.5
   |  |                          and El Ref      |
   |  |-Comp. ID=M1.6            values must     |-Comp. ID=C1.3
   |  |                             match--------|--> El Ref=M1.5
   |  |-Comp. ID=M1.7                            |-Comp. ID=C1.4
   |
   |-Trading Block. ID=M1.9
      |-Comp. ID=M1.10
      |-Comp. ID=M1.11
      |-Comp. ID=M1.12
      |-Comp. ID=M1.13

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-

                          Figure 9 Element References

  Note: Element Reference attributes are defined as "NMTOKEN" rather
  than "IDREF" (see [XML]). This is because an IDREF requires that the
  XML element referred to is in the same XML Document.  With IOTP this
  is not necessarily the case.

3.6 Extending IOTP

  Baseline IOTP defines a minimum protocol which systems supporting
  IOTP must be able to accept. As new versions of IOTP are developed,
  additional types of IOTP Transactions will be defined. In addition to
  this, Baseline and future versions of IOTP will support user
  extensions to IOTP through two mechanisms:





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  o  extra XML elements, and

  o  new values for existing IOTP codes.

3.6.1 Extra XML Elements

  The XML element and attribute names used within IOTP constitute an
  [XML Namespace] as identified by the xmlns attribute on the
  IotpMessage element. This allows IOTP to support the inclusion of
  additional XML elements within IOTP messages through the use of [XML
  Namespaces].

  Using XML Namespaces, extra XML elements may be included at any level
  within an IOTP message including:

  o  new Trading Blocks

  o  new Trading Components

  o  new XML elements within a Trading Component.

  The following rules apply:

  o  any new XML element must be declared according to the rules for
     [XML Namespaces]

  o  new XML elements which are either Trading Blocks or Trading
     Components must contain an ID attributes with an attribute name of
     ID.

  In order to make sure that extra XML elements can be processed
  properly, IOTP reserves the use of a special attribute,
  IOTP:Critical, which takes the values True or False and may appear in
  extra elements added to an IOTP message.

  The purpose of this attribute is to allow an IOTP aware application
  to determine if the IOTP transaction can safely continue.
  Specifically:

  o  if an extra XML element has an "IOTP:Critical" attribute with a
     value of "True" and an IOTP aware application does not know how to
     process the element and its child elements, then the IOTP
     transaction has a Technical Error (see section 4.1) and must fail.

  o  if an extra XML element has an "IOTP:Critical" attribute with a
     value of "False" then the IOTP transaction may continue if the
     IOTP aware application does not know how to process it. In this
     case:



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     -  any extra XML elements contained within an XML element defined
        within the IOTP namespace, must be included with that element
        whenever the IOTP XML element is used or copied by IOTP

     -  the content of the extra element must be ignored except that it
        must be included when it is used in the creation of a digest as
        part of the generation of a signature

  o  if an extra XML element has no "IOTP:Critical" attribute then it
     must be treated as if it had an "IOTP:Critical" attribute with a
     value of "True"

  o  if an XML element contains an "IOTP:Critical" attribute, then the
     value of that attribute is assumed to apply to all the child
     elements within that element

  In order to ensure that documents containing "IOTP:Critical" are
  valid, it is declared as part of the DTD for the extra element as:

  IOTP:Critical     (True | False ) 'True'

3.6.2 Opaque Embedded Data

  If IOTP is to be extended using Opaque Embedded Data then a Packaged
  Content Element (see section 3.7) should be used to encapsulate the
  data.

3.7 Packaged Content Element

  The Packaged Content element supports the concept of an embedded data
  stream, transformed to both protect it against misinterpretation by
  transporting systems and to ensure XML compatibility. Examples of its
  use in IOTP include:

  o  to encapsulate payment scheme messages, such as SET messages,

  o  to encapsulate a description of an order, a payment note, or a
     delivery note.

  In general it is used to encapsulate one or more data streams.

  This data stream has three standardised attributes that allow for
  identification, decoding and interpretation of the contents. Its
  definition is as follows.







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  <!ELEMENT PackagedContent (#PCDATA) >
  <!ATTLIST PackagedContent
   Name             CDATA     #IMPLIED
   Content          NMTOKEN   "PCDATA"
   Transform (NONE|BASE64)    "NONE" >

  Attributes:

  Name               Optional. Distinguishes between multiple
                     occurrences of Packaged Content Elements at the
                     same point in IOTP. For example:
                       <ABCD>
                         <PackagedContent Name='FirstPiece'>
                           snroasdfnas934k
                         </PackagedContent>
                         <PackagedContent Name='SecondPiece'>
                           dvdsjnl5poidsdsflkjnw45
                         </PackagedContent>
                       </ABCD>

                     The name attribute may be omitted, for example if
                     there is only one Packaged Content element.

  Content            This identifies what type of data is contained
                     within the Content of the Packaged Content
                     Element. The valid values for the Content
                     attribute are as follows:
                      o PCDATA. The content of the Packaged Content
                        Element can be treated as PCDATA with no
                        further processing.
                      o MIME. The content of the Packaged Content
                        Element is a complete MIME item. Processing
                        should include looking for MIME headers inside
                        the Packaged Content Element.
                      o MIME:mimetype. The content of the Packaged
                        Content Element is MIME content, with the
                        following header "Content-Type: mimetype".
                        Although it is possible to have MIME:mimetype
                        with the Transform attribute set to NONE, it is
                        far more likely to have Transform attribute set
                        to BASE64. Note that if Transform is NONE is
                        used, then the entire content must still
                        conform to PCDATA. Some characters will need to
                        be encoded either as the XML default entities,
                        or as numeric character entities.






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                      o XML. The content of the Packaged Content
                        Element can be treated as an XML document.
                        Entities and CDATA sections, or Transform set
                        to BASE64, must be used to ensure that the
                        Packaged Content Element contents are
                        legitimate PCDATA.

                     Values of the Content attribute are controlled
                     under the procedures defined in section 12 IANA
                     Considerations which also allows user defined
                     values to be defined.

  Transform          This identifies the transformation that has been
                     done to the data before it was placed in the
                     content. Valid values are:

                      o NONE. The PCDATA content of the Packaged
                        Content Element is the correct representation
                        of the data. Note that entity expansion must
                        occur first (i.e. replacement of &amp; and
                        &#9;) before the data is examined. CDATA
                        sections may legitimately occur in a Packaged
                        Content Element where the Transform attribute
                        is set to NONE.
                      o BASE64. The PCDATA content of the Packaged
                        Content Element represents a BASE64 encoding of
                        the actual content.

  Content:

  PCDATA             This is the actual data which has been embedded.
                     The format of the data and rules on how to decode
                     it are contained in the Content and the Transform
                     attributes

  Note that any special details, especially custom attributes, must be
  represented at a higher level.

3.7.1 Packaging HTML

  The packaged content may contain HTML. In this case the following
  conventions are followed:

  o  references to any documents, images or other things, such as
     sounds or web pages, which can affect the recipient's
     understanding of the data which is being packaged must refer to
     other Packaged Elements contained within the same parent element,
     e.g., an Order Description



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  o  if more than one Packaged Content element is included within a
     parent element in order to meet the previous requirement, then the
     Name attribute of the top level Packaged Content from which
     references to all other Packaged Elements can be determined,
     should have a value of Main

  o  relative references to other documents, images, etc. from one
     Packaged Content element to another are realised by setting the
     value of the relative reference to the Name attribute of another
     Packaged Content element at the same level and within the same
     parent element

  o  no external references that require the reference to be resolved
     immediately should be used. As this could make the HTML difficult
     or impossible to display completely

  o  [MIME] is used to encapsulate the data inside each Packaged
     Element.  This means that the information in the MIME header used
     to identify the type of data which has been encapsulated and
     therefore how it should be displayed.

  If the above conventions are not followed by, for example, including
  external references which must be resolved, then the recipient of the
  HTML should be informed.

  Note: As an implementation guideline the values of the Name
  Attributes allocated to Packaged Content elements should make it
  possible to extract each Packaged Content into a directory and then
  display the HTML directly

3.7.2 Packaging XML

  Support for XML is recommended. When XML needs to be displayed, for
  example to display the content of an Order Description to a Consumer,
  then implementers should follow the latest recommendations of the
  World Wide Web Consortium.

  Note: At the time of writing this specification, standards are under
  development that specify XML style sheets that show how XML documents
  should be displayed. See:

  o "Extensible Stylesheet Language (XSL) Specification" at
    http://www.w3.org/TR/WD-xsl, and

  o "Associating stylesheets with XML documents" at
    http://www.w3.org/TR/xml-stylesheet.





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  Once these standards become W3C "Recommendations", then it is
  anticipated that this specification will be amended if practical.

3.8 Identifying Languages

  IOTP uses [XML] Language Identification to specify which languages
  are used within the content and attributes of IOTP Messages.

  The following principles have been used in order to determine which
  XML elements contain an xml:lang Attributes:

  o  a mandatory xml:lang attribute is contained on every Trading
     Component which contains attributes or content which may need to
     be displayed or printed in a particular language

  o  an optional xml:lang attribute is included on child elements of
     these Trading Components. In this case the value of xml:lang, if
     present, overrides the value for the Trading Component.

  xml:lang attributes which follow these principles are included in the
  Trading Components and their child XML elements defined in section 7.

  A sender of a message, typically a Consumer can indicate a preference
  for a language, and a character set by specifying a list of preferred
  languages/character sets in a Message Id Component (see section
  3.3.2).  Note that there is no obligation on the receiver of such a
  message to respond using one of the listed languages/character sets
  as they may not have the technology to be able to do it. It also
  means that the ability to handle these lists is not a requirement for
  conformance to this specification. However the ability to respond,
  for example using one of the stated languages/character sets is
  likely to provide a better user experience.

3.9 Secure and Insecure Net Locations

  IOTP contains several "Net Locations" which identify places where,
  typically, IOTP Messages may be sent. Net Locations come in two
  types:

  o  "Secure" Net Locations which are net locations where privacy of
     data is secured using, for example, encryption methods such as
     [SSL/TLS], and

  o  "Insecure" Net Locations where privacy of data is not assured.

  Note that either a Secure Net Location or an Insecure Net Location or
  both must be present.




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  If only one of the two Net Locations is present, then the one present
  must be used.

  Where both types of net location are present then either may be used
  depending on the preference of the sender of the message.

3.10 Cancelled Transactions

  Any Trading Role involved in an IOTP transaction may cancel that
  transaction at any time.

3.10.1 Cancelling Transactions

  IOTP Transactions are cancelled by sending an IOTP message containing
  just a Cancel Block with an appropriate Status Component to the other
  Trading Role involved in the Trading Exchange.

  Note: The Cancel Block can be sent asynchronously of any other IOTP
  Message. Specifically it can be sent either before sending or after
  receiving an IOTP Message from the other Trading Role

  If an IOTP Transaction is cancelled during a Trading Exchange (i.e.
  the interval between sending a "request" block and receiving the
  matching "response" block) then the Cancel Block is sent to the same
  location as the next IOTP Message in the Trading Exchange would have
  been sent.

  If a Consumer cancels a transaction after a Trading Exchange has
  completed (i.e. the "response" block for the Trading Exchange has
  been received), but before the IOTP Transaction has finished then the
  Consumer sends a Cancel Block with an appropriate Status Component to
  the net location identified by the SenderNetLocn or
  SecureSenderNetLocn contained in the Protocol Options Component (see
  section 7.1) contained in the TPO Block (see section 8.1) for the
  transaction. This is normally the Merchant Trading Role.

  A Consumer should not send a Cancel Block after the IOTP Transaction
  has completed. Cancelling a complete transaction should be treated as
  a technical error.

  After cancelling the IOTP Transaction, the Consumer should go to the
  net location specified by the CancelNetLocn attribute contained in
  the Trading Role Element for the Organisation that was sent the
  Cancel Block.

  A non-Consumer Trading Role should only cancel a transaction:

  o after a request block has been received and



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  o before the response block has been sent

  If a non-Consumer Trading Role cancels a transaction at any other
  time it should be treated by the recipient as an error.

3.10.2 Handling Cancelled Transactions

  If a Cancel Block is received by a Consumer at a point in the IOTP
  Transaction when cancellation is allowed, then the Consumer should
  stop the transaction.

  If a Cancel Block is received by a non-Consumer role, then the
  Trading Role should anticipate that the Consumer may go to the
  location specified by the CancelNetLocn attribute contained in the
  Trading Role Element for the Trading Role.

4. IOTP Error Handling

  IOTP is designed as a request/response protocol where each message is
  composed of a number of Trading Blocks which contain a number of
  Trading Components. There are several interrelated considerations in
  handling errors, re-transmissions, duplicates, and the like. These
  factors mean IOTP aware applications must manage message flows more
  complex than the simple request/response model. Also a wide variety
  of errors can occur in messages as well as at the transport level or
  in Trading Blocks or Components.

  This section describes at a high level how IOTP handles errors,
  retries and idempotency. It covers:

  o  the different types of errors which can occur. This is divided
     into:

     -  "technical errors" which are independent of the purpose of the
        IOTP Message,

     -  "business errors" which indicate that there is a problem
        specific to the process (e.g., payment or delivery) which is
        being carried out, and

  o  the depth of the error which indicates whether the error is at the
     transport, message or block/component level

  o  how the different trading roles should handle the different types
     of messages which they may receive.






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4.1 Technical Errors

  Technical Errors are those which are independent of the meaning of
  the message. This means, they can affect any attempt at IOTP
  communication.  Typically they are handled in a standard fashion with
  a limited number of standard options for the user. Specifically these
  are:

  o retrying the transmission, or

  o cancelling the transaction.

  When communications are operating sufficiently well, a technical
  error is indicated by an Error Component (see section 7.21) in an
  Error Block (see section 8.17) sent by the party which detected the
  error in an IOTP message to the party which sent the erroneous
  message.

  If communications are too poor, a message which was sent may not
  reach its destination. In this case a time-out might occur.

  The Error Codes associated with Technical Errors are recorded in the
  Error Component which lists all the different technical errors which
  can be set.

4.2 Business Errors

  Business Errors may occur when the IOTP messages are "technically"
  correct. They are connected with a particular process, for example,
  an offer, payment, delivery or authentication, where each process has
  a different set of possible business errors.

  For example, "Insufficient funds" is a reasonable payment error but
  makes no sense for a delivery while "Back ordered" is a reasonable
  delivery error but not meaningful for a payment. Business errors are
  indicated in the Status Component (see section 7.16) of a "response
  block" of the appropriate type, for example a Payment Response Block
  or a Delivery Response Block. This allows whatever additional
  response related information is needed to accompany the error
  indication.

  Business errors must usually be presented to the user so that they
  can decide what to do next. For example, if the error is insufficient
  funds in a Brand Independent Offer (see section 9.1.2.2), the user
  might wish to choose a different payment instrument/account of the
  same brand or a different brand or payment system. Alternatively, if





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  the IOTP based implementation allows it and it makes sense for that
  instrument, the user might want to put more funds into the
  instrument/account and try again.

4.3 Error Depth

  The three levels at which IOTP errors can occur are the transport
  level, the message level, and the block level. Each is described
  below.

4.3.1 Transport Level

  This level of error indicates a fundamental problem in the transport
  mechanism over which the IOTP communication is taking place.

  All transport level errors are technical errors and are indicated by
  either an explicit transport level error indication, such as a "No
  route to destination" error from TCP/IP, or by a time out where no
  response has been received to a request.

  The only reasonable automatic action when faced with transport level
  errors is to retry and, after some number of automatic retries, to
  inform the user.

  The explicit error indications that can be received are transport
  dependent and the documentation for the appropriate IOTP Transport
  supplement should be consulted for errors and appropriate actions.

  Appropriate time outs to use are a function of both the transport
  being used and of the payment system if the request encapsulates
  payment information. The transport and payment system specific
  documentation should be consulted for time out and automatic retry
  parameters.  Frequently there is no way to directly inform the other
  party of transport level errors but they should generally be logged
  and if automatic recovery is unsuccessful and there is a human user,
  the user should be informed.

4.3.2 Message Level

  This level of error indicates a fundamental technical problem with an
  entire IOTP message. For example, the XML is not "Well Formed", or
  the message is too large for the receiver to handle or there are
  errors in the Transaction Reference Block (see section 3.3) so it is
  not possible to figure out what transaction the message relates to.

  All message level errors are technical errors and are indicated by
  Error Components (see section 7.21) sent to the other party. The
  Error Component includes a Severity attribute which indicates whether



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  the error is a Warning and may be ignored, a TransientError which
  indicates that a retry may resolve the problem or a HardError in
  which case the transaction must fail.

  The Technical Errors (see section 7.21.2 Error Codes) that are
  Message Level errors are:

  o  XML not well formed. The document is not well formed XML (see
     [XML])

  o  XML not valid. The document is not valid XML (see [XML])

  o  block level technical errors (see section 4.3.3) on the
     Transaction Reference Block (see section 3.3) and the Signature
     Block only. Checks on these blocks should only be carried out if
     the XML is valid

  Note that checks on the Signature Block include checking, where
  possible, that each Signature Component is correctly calculated. If
  the Signature is incorrectly calculated then the data that should
  have been covered by the signature can not be trusted and must be
  treated as erroneous. A description of how to check a signature is
  correctly calculated is contained in section 6.2.

4.3.3 Block Level

  A Block level error indicates a problem with a block or one of its
  components in an IOTP message (apart from Transaction Reference or
  Signature Blocks). The message has been transported properly, the
  overall message structure and the block/component(s) including the
  Transaction Reference and Signature Blocks are meaningful but there
  is some error related to one of the other blocks.

  Block level errors can be either:

  o  technical errors, or

  o  business errors

  Technical Errors are further divided into:

  o  Block Level Attribute and Element Checks, and

  o  Block and Component Consistency Checks

  o  Transient Technical Errors





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  If a technical error occurs related to a block or component, then an
  Error Component is generated for return.

4.3.3.1 Block Level Attribute and Element Checks

  Block Level Attribute and Element Checks occur only within the same
  block. Checks which involve cross-checking against other blocks are
  covered by Block and Component Consistency Checks.

  The Block Level Attribute & Element checks are:

  o  checking that each attribute value within each element in a block
     conforms to any rules contained within this IOTP specification

  o  checking that the content of each element conforms to any rules
     contained within this IOTP specification

  o  if the previous checks are OK, then checking the consistency of
     attribute values and element content against other attribute
     values or element content within any other components in the same
     block.

4.3.3.2 Block and Component Consistency Checks

  Block and Component Consistency Checks consist of:

  o  checking that the combination of blocks and/or components present
     in the IOTP Message are consistent with the rules contained within
     this IOTP specification

  o  checking for consistency between attributes and element content
     within the blocks within the same IOTP message.

  o  checking for consistency between attributes and elements in blocks
     in this IOTP message and blocks received in earlier IOTP messages
     for the same IOTP transaction

  If the block passes the "Block Level Attribute and Element Checks"
  and the "Block and Component Consistency Checks" then it is processed
  either by the IOTP Aware application or perhaps by some "back-end"
  system such as a payment server.

4.3.3.3 Transient Technical Errors

  During the processing of the Block some temporary failure may occur
  that can potentially be recovered by the other trading role re-
  transmitting, at some slightly later time, the original message that
  they sent.  In this case the other role is informed of the Transient



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  Error by sending them an Error Component (see section 7.21) with the
  Severity Attribute set to TransientError and the MinRetrySecs
  attribute set to some value suitable for the Transport Mechanism
  and/or payment protocol being used (see appropriate Transport and
  payment protocol Supplements).

  Note that transient technical errors can be generated by any of the
  Trading Roles involved in transaction.

4.3.3.4 Block Level Business Errors

  If a business error occurs in a process such as a Payment or a
  Delivery, then the appropriate type of response block is returned
  containing a Status Component (see section 7.16) with the
  ProcessState attribute set to Failed and the CompletionCode
  indicating the nature of the problem.

  Some business errors may be "transient" in that the Consumer role may
  be able to recover and complete the transaction in some other way.
  For example if the Credit Card that a consumer provided had
  insufficient funds for a purchase, then the Consumer may recover by
  using a different credit card.

  Recovery from "transient" business errors is dependent on the
  CompletionCode. See the definition of the Status Component for what
  is possible.

  Note that no Error Component or Error Block is generated for business
  errors.

4.4 Idempotency, Processing Sequence, and Message Flow

  IOTP messages are actually a combination of blocks and components as
  described in 3.1.1 IOTP Message Structure. Especially in future
  extensions of IOTP, a rich variety of combinations of such blocks and
  components can occur. It is important that the multiple
  transmission/receipt of the "same" request for an action that will
  change state does not result in that action occurring more than once.
  This is called idempotency. For example, a customer paying for an
  order would want to pay the full amount only once. Most network
  transport mechanisms have some probability of delivering a message
  more than once or not at all, perhaps requiring retransmission. On
  the other hand, a request for status can reasonably be repeated and
  should be processed fresh each time it is received.







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  Correct implementation of IOTP can be modelled by a particular
  processing order as detailed below. Any other method that is
  indistinguishable in the messages sent between the parties is equally
  acceptable.

4.5 Server Role Processing Sequence

  "Server roles" are any Trading Role which is not the Consumer role.
  They are "Server roles" since they typically receive a request which
  they must service and then produce a response. However server roles
  can also initiate transactions. More specifically Server Roles must
  be able to:

  o  Initiate a transaction (see section 4.5.1). These are divided
     into:

     -  payment related transactions and

     -  infrastructure transactions

  o  Accept and process a message received from another role (see
     section 4.5.2). This includes:

     -  identifying if the message belongs to a transaction that has
        been received before

     -  handling duplicate messages

     -  generating Transient errors if the servers that process the
        input message are too busy to handle it

     -  processing the message if it is error free, authorised and, if
        appropriate, producing a response to send back to the other
        role

  o  Cancel a current transaction if requested (see section 4.5.3)

  o  Re-transmit messages if a response was expected but has not been
     received in a reasonable time (see section 4.5.4).

4.5.1 Initiating Transactions

  Server Roles may initiate a variety of different types of
  transaction.  Specifically:

  o  an Inquiry Transaction (see section 9.2.1)

  o  a Ping Transaction (see section 9.2.2)



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  o  an Authentication Transaction (see section 9.1.6)

  o  a Payment Related Transaction such as:

     -  a Deposit (see section 9.1.7)

     -  a Purchase (see section 9.1.8)

     -  a Refund (see section 9.1.9)

     -  a Withdrawal (see section 9.1.10)

     -  a Value Exchange (see section 9.1.11)

4.5.2 Processing Input Messages

  Processing input messages involves the following:

  o  checking the structure and identity of the message

  o  checking for and handling duplicate messages

  o  processing non-duplicate original messages which includes:

     -  checking for errors, then if no errors are found

     -  processing the message to produce an output message if
        appropriate

  Each of these is discussed in more detail below.

4.5.2.1 Checking Structure and Message Identity

  It is critical to check that the message is "well formed" XML and
  that the transaction identifier (IotpTransId attribute on the TransId
  Component) within the IOTP message can be successfully identified
  since an IotpTransId will be needed to generate a response.

  If the input message is not well formed then generate an Error
  Component with a Severity of HardError and ErrorCode of
  XmlNotWellFrmd.

  If the message is well formed but the IotpTransId cannot be
  identified then generate an ErrorComponent with:

  o  a Severity of HardError and an ErrorCode of AttMissing,





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  o  a PackagedContent containing "IotpTransId" - the missing
     attribute.

  Insert the Error Component inside an Error Block with a new
  TransactionId component with a new IotpTransId and return it to the
  sender of the original message.

4.5.2.2 Checking/Handling Duplicate Messages

  If the input message can be identified as potentially a valid input
  message then check to see if an "identical" input message has been
  received before. Identical means that all blocks, components,
  elements, attribute values and element content in the input message
  are the same.

  Note: The recommended way of checking for identical messages is to
  check for equal values of their [DOM-HASH]

  If an identical message has been received before then check to see if
  the processing of the previous message has completed.

  If processing has not completed then generate an Error Component with
  a Severity of Transient Error and an Error Code of MsgBeingProc to
  indicate the message is being processed and send it back to the
  sender of the Input Message requesting that the original message be
  resent after an appropriate period of time.

  Otherwise, if processing has completed and resulted in an output
  message then retrieve the last message that was sent and send it
  again.

  If the message is not a duplicate then it should be processed.

4.5.2.3 Processing Non-Duplicate Message

  Once it's been established that the message is not a duplicate, then
  it can be processed. This involves:

  o  checking that a server is available to handle the message,
     generating a Transient Error if it is not

  o  checking the Transaction is Not Already in error or cancelled

  o  validating the input message. This includes:

     -  checking for message level errors

     -  checking for block level errors



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     -  checking any encapsulated data

  o  checking for errors in the sequence that blocks have been received

  o  generating error components for any errors that result

  o  if neither hard errors nor transient errors result, then
     processing the message and generating an output message, if
     required, for return to the sender of the Input Message

  Note: This approach to handling of duplicate input messages means, if
  absolutely "identical" messages are received then absolutely
  "identical" messages are returned. This also applies to Inquiry and
  Ping transactions when in reality the state of a transaction or the
  processing ability of the servers may have changed. If up-to-date
  status of transactions or servers is required, then an IOTP
  transaction with a new value for the ID attribute of the MsgId
  component must be used.

  Each of the above steps is discussed below.

  CHECKING A SERVER IS AVAILABLE

  The process that is handling the input message should check that the
  rest of the system is not so busy that a response in a reasonable
  time cannot be produced.

  If the server is too busy, then it should generate an Error Component
  with a Severity of Transient Error and an Error Code of SystemBusy
  and send it back to the sender of the Input Message requesting that
  the original message be resent after an appropriate period of time.

  Note: Some servers may occasionally become very busy due to
  unexpected increases in workload. This approach allows short peaks in
  workloads to be handled by delaying the input of messages by asking
  the sender of the message to resubmit later.

  CHECKING THE TRANSACTION IS NOT ALREADY IN ERROR OR CANCELLED

  Check that:

  o  previous messages received or sent did not contain or result in
     Hard Errors, and

  o  the Transaction has not been cancelled by either the Consumer or
     the Server Trading Role





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  If it has then, ignore the message. A transaction with hard errors or
  that has been cancelled, cannot be restarted.

  CHECK FOR MESSAGE AND BLOCK LEVEL ERRORS

  If the transaction is still OK then check for message level errors.
  This involves:

  o  checking the XML is valid

  o  checking that the elements, attributes and content of the
     Transaction Reference Block are without error and conform to this
     specification

  o  checking the digital signature which involves:

     -  checking that the Signature value is correctly calculated, and

     -  the hash values in the digests are correctly calculated where
        the source of the hash value is available.

  Checking for block level errors involves:

  o  checking within each block (apart from the Transaction Reference
     Block) that:

     -  the attributes, elements and element contents are valid

     -  the values of the attributes, elements and element contents are
        consistent within the block

  o  checking that the combination of blocks are valid

  o  checking that the values of the attribute, elements and element
     contents are consistent between the blocks in the input message
     and blocks in earlier messages either sent or received. This
     includes checking that the presence of a block is valid for a
     particular transaction type

  If the message contains any encapsulated data, then if possible check
  the encapsulated data for errors using additional software to check
  the data where appropriate.

4.5.2.4 Check for Errors in Block Sequence

  Note: For reasons of brevity, the following explanations of how to
  check for errors in Block sequence, the phrase "refers to an IOTP
  transaction" is interpreted as "is contained in an IOTP Message where



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  the Trans Ref Block contains an IotpTransId that refers to". So, for
  example, " If an Error or Cancel Block refers to an IOTP transaction
  that is not recognised then ..."  should be interpreted as " If an
  Error or Cancel Block is contained in an IOTP Message where the Trans
  Ref Block contains an IotpTransId that refers to an IOTP transaction
  that is not recognised then ...

  Errors in the sequence that blocks arrive depends on the block.
  Blocks where checking for sequence is required are:

  o  Error and Cancel Blocks. If an Error or Cancel Block refers to an
     IOTP transaction that is not recognised then it is a Hard Error.
     Do not return an error if Error or Cancel Blocks have been
     received for the IOTP Transaction before to avoid looping.

  o  Inquiry Request and Response Blocks. If an Inquiry Request or an
     Inquiry Response Block refers to an IOTP transaction that is not
     recognised then it is a Hard Error

  o  Authentication Request Block. If an Authentication Request Block
     refers to an IOTP transaction that is recognised it is a Hard
     Error

  o  Authentication Response Block. Check as follows:

     -  if an Authentication Response Block does not refer to an IOTP
        transaction that is recognised it is a Hard Error, otherwise

     -  if the Authentication Response Block doesn't refer to an
        Authentication Request that had been previously sent then it is
        a Hard Error, otherwise

     -  if an Authentication Response for the same IOTP transaction has
        been received before and the Authentication was successful then
        it is a Hard Error.

  o  Authentication Status Block. Check as follows:

     -  if an Authentication Status Block does not refer to an IOTP
        transaction that is recognised it is a Hard Error, otherwise

     -  if the Authentication Status Block doesn't refer to an
        Authentication Response that had been previously sent then it
        is a Hard Error, otherwise

     -  if an Authentication Status for the same IOTP transaction has
        been received before then it is a Warning Error




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  o  TPO Selection Block (Merchant only). Check as follows:

     -  if the TPO Selection Block doesn't refer to an IOTP Transaction
        that is recognised then it is a Hard Error, otherwise

     -  if the TPO Selection Block refers to an IOTP Transaction where
        a TPO Block and Offer Response (in one message) had previously
        been sent then it is a Hard Error, otherwise

     -  if the TPO Selection Block does not refer to an IOTP
        Transaction where a TPO Block only (i.e. without an Offer
        Response) had previously been sent then it is a Hard Error,
        otherwise

     -  if a TPO Selection Block for the same TPO Block has been
        received before then it is a Hard Error

  o  Payment Request Block (Payment Handler only). Check as follows:

     -  if the Payment Request Block refers to an IOTP Transaction that
        is not recognised then its OK, otherwise

     -  if the Payment Request Block refers to IOTP Transaction that
        was not for a Payment then it is a Hard Error, otherwise

     -  if there was a previous payment that failed with a non-
        recoverable Completion Code then it is a Hard Error, otherwise

     -  if a previous payment is still in progress then it is a Hard
        Error

  o Payment Exchange Block (Payment Handler only). Check as follows:

     -  if the Payment Exchange Block doesn't refer to an IOTP
        Transaction that is recognised then it is a Hard Error,
        otherwise

     -  if the Payment Exchange doesn't refer to an IOTP Transaction
        where a Payment Exchange had previously been sent then it a
        Hard Error

  o  Delivery Request (Delivery Handler Only). If the Delivery Request
     Block refers to an IOTP Transaction that is recognised by the
     Server then it is a Hard Error







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  If any Error Components have been generated then collect them into an
  Error Block for sending to the sender of the Input message. Note that
  Error Blocks should be sent back to the sender of the message and to
  the ErrorLogNetLocn for the Trading Role of the sender if one is
  specified.

  Note: The above checking on the sequence of Authentication Responses
  and Payment Requests supports the Consumer re-submitting a repeat
  action request since the previous one failed, for example:

  o  because they did not know the correct response (e.g., a password)
     on an authentication or,

  o  they were unable to pay as there were insufficient funds on a
     credit card

  PROCESS THE ERROR FREE INPUT MESSAGE

  If the input message passes the previous checks then it can be
  processed to produce an output message if required. Note that:

  o  Inquiry Requests on Ping Transactions should be ignored

  o  if the Input message contains an Error Block with a Transient
     Error then wait for the required time then resend the previous
     message, if a response to the earlier message has not been
     received

  o  if the input message contains a Error Component with a  HardError
     or a Cancel Block then stop all further processing of the
     transaction. This includes suppressing the sending of any messages
     currently being generated or responding to any new non-duplicate
     messages that are received

  o  processing of encapsulated messages (e.g., Payment Protocol
     Messages) may result in additional transient errors

  o  a digital signature can only safely be generated once all the
     blocks and components have been generated and it is known which
     elements in the message need to be signed.

  If an output message is generated then it should be saved so that it
  can be resent as required if an identical input message is received
  again.  Note that output messages that contain transient errors are
  not saved so that they can be processed afresh when the input message
  is received again.





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4.5.3 Cancelling a Transaction

  This process is used to cancel a transaction running on an IOTP
  server.  It is initiated by some other process as a result of an
  external request from another system or server that is being run by
  the same Trading Role.  The processing required is as follows:

  o  if the IotpTransId of the transaction to be cancelled is not
     recognised, or complete then fail the request, otherwise

  o  if the IotpTransId refers to a Ping Transaction then fail the
     request, otherwise

  o  determine which Document Exchange to cancel and generate a Cancel
     Block and send it to the other party

  Note: Cancelling a transaction on an IOTP server typically arises for
  a business reason. For example a merchant may have attempted
  authentication several times without success and as a result decides
  to cancel the transaction. Therefore the process that decides to take
  this action needs to send a message from the process/server that made
  the business decision to the IOTP server with the instruction that
  the IOTP transaction should be cancelled.

4.5.4 Retransmitting Messages

  The server should periodically check for transactions where a message
  is expected in return but none has been received after a time that is
  dependent on factors such as:

  o  the Transport Mechanism being used;

  o  the time required to process encapsulated messages (e.g., Payment
     messages) and

  o  whether or not human input is required.

  If no message has been received the original message should be
  resent.  This should occur up to a maximum number of times dependent
  on the reliability of the Transport Mechanism being used.

  If no response is received after the required time then the
  Transaction should be "timed out". In this case, set the process
  state of the transaction to Failed, and a completion code of either:

  o  TimedOutRcvr if the transaction can potentially recovered later,
     or




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  o  TimedOutNoRcvr if the transaction is non-recoverable

4.6 Client Role Processing Sequence

  The "Client role" in IOTP is the Consumer Trading Role.

  Note: A company or Organisation that is a Merchant, for example, may
  take on the Trading Role of a Consumer when making purchases or
  downloading or withdrawing electronic cash.

  More specifically the Consumer Role must be able to:

  o  Initiate a transaction (see section 4.6.1). These are divided
     into:

     -  payment related transactions and

     -  infrastructure transactions

  o  Accept and process a message received from another role (see
     section 4.6.2). This includes:

     -  identifying if the message belongs to a transaction that has
        been received before

     -  handling duplicate messages

     -  generating Transient errors if the servers that process the
        input message are too busy to handle it

     -  processing the message if it is error free and, if appropriate,
        producing a response to send back to the other role

  o  Cancel a current transaction if requested, for example by the User
     (see section 4.6.3)

  o  Re-transmit messages if a response was expected but has not been
     received in a reasonable time (see section 4.6.4).

4.6.1 Initiating Transactions

  The Consumer Role may initiate a number of different types of
  transaction. Specifically:

  o an Inquiry Transaction (see section 9.2.1)

  o a Ping Transaction (see section 9.2.2)




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  o an Authentication Transaction (see section 9.1.6)

4.6.2 Processing Input Messages

  Processing of Input Messages for a Consumer Role is the same as for
  an IOTP Server (see section 4.5.2) except in the area of checking for
  Errors in Block Sequence (for an IOTP Server see section 4.5.2.4).
  This is described below

  Note: The description of the processing for an IOTP Server includes
  consideration of multi-threading of input messages and multi-tasking
  of requests. For the Consumer Role - particularly if running on a
  stand-alone system such as a PC - use of multi-threading is a
  decision of the implementer of the consumer role IOTP solution.

4.6.2.1 Check for Errors in Block Sequence

  The handling of the following blocks is the same as for an IOTP
  Server (see section 4.5.2.4) except that the Consumer Role is
  substituted for IOTP Server Role:

  o Error and Cancel Blocks,

  o Inquiry Request and Response Blocks,

  o Authentication Request, Response and Status Blocks.

  For the other blocks a Consumer role might receive, the potential
  errors in the sequence that blocks arrive depends on the block.
  Blocks where checking for sequence is required are:

  o  TPO Block. Check as follows:

     -  if the input message also contains an Authentication Request
        block and an Offer Response Block then there is a Hard Error,
        otherwise

     -  if the input message also contains an Authentication Request
        block and Authentication Status block then there is Hard Error
        otherwise,


     -  if the input message also contains an Authentication Request
        block and the IOTP Transaction is recognised by the Consumer
        role's system, then there is a Hard Error, otherwise






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     -  if the input message also contains an Authentication Status
        block and the IOTP Transaction is not recognised by the
        Consumer role's system then there is a Hard Error, otherwise

     -  if input message also contains an Authentication Status Block
        and the Authentication Status Block has not been sent after an
        earlier Authentication Response message then there is a hard
        error

     -  if input message also contains an Offer Response Block and the
        IOTP Transaction is recognised by the Consumer role's system
        then there is a Hard Error, otherwise

     -  if the TPO Block occurs on its own and the IOTP Transaction is
        recognised by the Consumer role's system then there is a Hard
        Error

  o Offer Response Block. Check as follows:

     -  if the Offer Response Block is part of a Brand Independent
        Offer Exchange (see section 9.1.2.2) then there is no sequence
        checking as it is part of the first message received, otherwise

     -  if the Offer Response Block is not part of an IOTP Transaction
        that is recognised by the Consumer role then there is a Hard
        Error, otherwise

     -  if the Offer Response Block does not refer to an IOTP
        transaction where a TPO Selection Block was the last message
        sent then there is a Hard Error

  o  Payment Exchange Block. Check as follows:

     -  if the Payment Exchange Block doesn't refer to an IOTP
        Transaction that is recognised by the Consumer role's system
        then there is a Hard Error, otherwise

     -  if the Payment Exchange doesn't refer to an IOTP Transaction
        where either a Payment Request or a Payment Exchange block was
        most recently sent then there is a Hard Error

  o  Payment Response Block. Check as follows:

     -  if the Payment Response Block doesn't refer to an IOTP
        Transaction that is recognised by the Consumer role's system
        then there is a Hard Error, otherwise





Burdett                      Informational                     [Page 73]

RFC 2801                       IOTP/1.0                       April 2000


     -  if the Payment Response doesn't refer to an IOTOP Transaction
        where either a Payment Request or a Payment Exchange block was
        most recently sent then there is a Hard Error

  o  Delivery Response Block. Check as follows:

     -  if the Delivery Response Block doesn't refer to an IOTP
        Transaction that is recognised by the Consumer role's system
        then there is a Hard Error, otherwise

     -  If the Delivery Response doesn't refer to an IOTP Transaction
        where either a Payment Request or a Payment Exchange block was
        most recently sent then there is a Hard Error

4.6.3 Cancelling a Transaction

  This process cancels a current transaction on an Consumer role's
  system as a result of an external request from the user, or another
  system or server in the Consumer's role. The processing is the same
  as for an IOTP Server (see section 4.5.3).

4.6.4 Retransmitting Messages

  The process of retransmitting messages is the same as for an IOTP
  Server (see section 4.5.4).

5. Security Considerations

  This section considers, from an IETF perspective how IOTP addresses
  security. The next section (see section 6. Digital Signatures and
  IOTP) describes how IOTP uses Digital Signatures when these are
  needed.

  This section covers:

  o determining whether to use digital signatures

  o data privacy, and

  o payment protocol security.

5.1 Determining whether to use digital signatures

  The use of digital signatures within IOTP are entirely optional. IOTP
  can work successfully entirely without the use of digital signatures.

  Ultimately it is up to the Merchant, or other trading role, to decide
  whether IOTP Messages will include signatures, and for the Consumer



Burdett                      Informational                     [Page 74]

RFC 2801                       IOTP/1.0                       April 2000


  to decide whether carrying out a transaction without signatures is an
  acceptable risk. If Merchants discover that transactions without
  signatures are not being accepted, then they will either:

  o start using signatures,

  o find a method of working which does not need signatures, or

  o accept a lower volume and value of business.

  A non-exhaustive list of the reasons why digital signatures might be
  used follows:

  o  the Merchant (or other trading role) wants to demonstrate that
     they can be trusted. If, for example, a merchant generates an
     Offer Response Signature (see section 7.19.2) using a certificate
     from a trusted third party, known to the Consumer, then the
     Consumer can check the signature and certificate and so more
     reasonably rely on the offer being from the actual Organisation
     the Merchant claims to be. In this case signatures using
     asymmetric cryptography are likely to be required

  o  the Merchant, or other Trading Role, want to generate a record of
     the transaction that is fit for a particular purpose. For example,
     with appropriate trust hierarchies, digital signatures could be
     checked by the Consumer to determine:

     -  if it would be accepted by tax authorities as a valid record of
        a transaction, or

     -  if some warranty, for example from a "Better Business Bureau"
        orsimilar was being provided

  o  the Payment Handler, or Delivery Handler, needs to know that the
     request is unaltered and authorised. For example, in IOTP, details
     of how much to pay is sent to the Consumer in the Offer Response
     and then forwarded to the Payment Handler in a Payment Request. If
     the request is not signed, the Consumer could change the amount
     due by, for example, removing a digit. If the Payment Handler has
     no access to the original payment information in the Offer
     Response, then, without signatures, the Payment Handler cannot be
     sure that the data has not been altered. Similarly, if the payment
     information is not digitally signed, the Payment Handler cannot be
     sure who is the Merchant that is requesting the payment

  o  a Payment Handler or Delivery Handler wants to provide a non-
     refutable record of the completion status of a Payment or
     Delivery. If a Payment Response or Delivery Response is signed,



Burdett                      Informational                     [Page 75]

RFC 2801                       IOTP/1.0                       April 2000


     then the Consumer can later use the record of the Payment or
     Delivery to prove that it occurred.  This could be used, for
     example, for customer care purposes.

  A non-exhaustive list of the reasons why digital signatures might not
  be used follows:

  o  trading roles are combined therefore changes to data made by the
     consumer can be detected. One of the reasons for using signatures
     is so that one trading role can determine if data has been changed
     by the Consumer or some other party. However if the trading roles
     have access to the necessary data, then it might be possible to
     compare, for example, the payment information in the Payment
     Request with the payment information in the Offer Response. Access
     to the data necessary could be realised by, for example, the
     Merchant and Payment Handler roles being carried out by the same
     Organisation on the same system, or the Merchant and Payment
     Handler roles being carried out on different systems but the
     systems can communicate in some way. (Note this type of
     communication is outside the current scope of IOTP)

  o  the processing cost of the cryptography is too high. For example,
     if a payment is being made of only a few cents, the cost of
     carrying out all the cryptography associated with generating and
     checking digital signatures might make the whole transaction
     uneconomic. Co-locating trading roles, could help avoid this
     problem.

5.2 Symmetric and Asymmetric Cryptography

  The advantage of using symmetric keys with IOTP is that no Public Key
  Infrastructure need be set up and just the Merchant, Payment Handler
  and Delivery Handler need to agree on the shared secrets to use.

  However the disadvantage of symmetric cryptography is that the
  Consumer cannot easily check the credentials of the Merchant, Payment
  Handler, etc. that they are dealing with. This is likely to reduce,
  somewhat, the trust that the Consumer will have carrying out the
  transaction.

  However it should be noted that even if asymmetric cryptography is
  being used, the Consumer does not NEED to be provided with any
  digital certificates as the integrity of the transaction is
  determined by, for example, the Payment Handler checking the Offer
  Response Signature copied to the Payment Request.

  Note that symmetric, asymmetric or both types of cryptography may be
  used in a single transaction.



Burdett                      Informational                     [Page 76]

RFC 2801                       IOTP/1.0                       April 2000


5.3 Data Privacy

  Privacy of information is provided by sending IOTP Messages between
  the various Trading Roles using a secure channel such as [SSL/TLS].
  Use of a secure channel within IOTP is optional.

5.4 Payment Protocol Security

  IOTP is designed to be completely blind to the payment protocol being
  used to effect a payment. From the security perspective, this means
  that IOTP neither helps, nor hinders, the achievement of payment
  security.

  If it is necessary to consider payment security from an IOTP
  perspective, then this should be included in the payment protocol
  supplement which describes how IOTP supports that payment protocol.

  However what IOTP is designed to do is to use digital signatures to
  bind together the record, contained in a "response" message, of each
  trading exchange in a transaction. For example IOTP can bind
  together: an Offer, a Payment and a Delivery.

6. Digital Signatures and IOTP

  IOTP can work successfully without using any digital signatures
  although in an open networking environment it will be less secure -
  see 5.  Security Considerations for a description of the factors that
  need to be considered.

  However, this section describes how to use digital signatures in the
  many situations when they will be needed. Topics covered are:

  o  an overview of how IOTP uses digital signatures

  o  how to check a signature is correctly calculated

  o  how Payment Handlers and Delivery Handlers check they can carry
     out payments or deliveries on behalf of a Merchant.

6.1 How IOTP uses Digital Signatures

  In general, signatures when used with IOTP:

  o  are always treated as IOTP Components (see section 7)

  o  contain digests of one or more IOTP Components or Trading Blocks,
     possibly including other Signature Components, in any IOTP message
     within the same IOTP Transaction



Burdett                      Informational                     [Page 77]

RFC 2801                       IOTP/1.0                       April 2000


  o  identify:

     -  which Organisation signed (originated) the signature, and

     -  which Organisation(s) should process the signature in order to
        check that the Action the Organisation should take can occur.

  Digital certificates may be associated with digital signatures if
  asymmetric cryptography is being used. However if symmetric
  cryptography is being used, then the digital certificate will be
  replaced by some identifier of the secret key to use.








































Burdett                      Informational                     [Page 78]

RFC 2801                       IOTP/1.0                       April 2000


  The way in which Signatures Components digest one or more elements is
  illustrated in the figure below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

IOTP MESSAGE                                  SIGNATURE COMPONENT

IOTP Message                                   Signature Id = P1.3
 |-Trans Ref Block        digest TransRefBlk   |-Manifest
 |  |      ID=P1.1-----------------------------|->|-Digest of P1.1--
 |  |-Trans Id Comp       digest TransIdComp   |  |                 |
 |  |     ID = M1.2----------------------------|->|-Digest of M1.2--|
 |  |-Msg Id Comp.           digest Signature  |  |                 |
 |  |      ID = P1          -------------------|->|-Digest of M1.5--|
 |                         |   digest element  |  |                 |
 |-Signatures Block        |  -----------------|->|-Digest of M1.7--|
 |  |       ID=P1.2        | |  digest element |  |                 |
 |  |-Signature ID=P1.3    | |  ---------------|->|-Digest of C1.4--|
 |  |-Signature ID=M1.5----  | |               |  |                 |
 |  |-Signature ID=P1.4      | | Points to     |   -RecipientInfo*  |
 |  |-Certificate ID=M1.6<---|-|---------------|------CertRef=M1.6  |
 |  |                        | | Certs to use  |  Sig.ValueRef=P1.4 |
 |  |                        | |               |        |           |
 |  |                        | |               |        |           |
 |-Trading Block. ID=P1.5    | |               |        v           |
 |  |-Comp. ID=M1.7----------  |                -Value* ID=P1.4:    |
 |  |                          |                   JtvwpMdmSfMbhK<--
 |  |-Comp. ID=P1.6            |                   r1Ln3vovbMQttbBI
 |  |                          |                   J8pxLjoSRfe1o6k
 |  |-Comp. ID=C1.4------------                    OGG7nTFzTi+/0<-
 |  |-Comp. ID=C1.5
                            Digital signature of Manifest element
                            using certificate identified by CertRef

  Elements that are digested can be in any IOTP Message
       within the same IOTP Transaction
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                        Figure 10 Signature Digests












Burdett                      Informational                     [Page 79]

RFC 2801                       IOTP/1.0                       April 2000


  Note: The classic example of one signature signing another in IOTP,
  is when an Offer is first signed by a Merchant creating an "Offer
  Response" signature, which is then later signed by a Payment Handler
  together with a record of the payment creating a "Payment Receipt"
  signature. In this way, the payment in an IOTP Transaction is bound
  to the Merchant's offer.

  Note that one Manifest may be associated with multiple signature
  "Value" elements where each Value element contains a digital
  signature over the same Manifest, perhaps using the same (or
  different) signature algorithm but using a different certificate or
  shared secret key. Specifically it will allow the Merchant to agree
  on different shared secrets keys with their Payment Handler and
  Delivery Handler.

  The detailed definitions of a Signature component are contained in
  section 7.19.

  The remainder of this section contains:

  o  an example of how IOTP uses signatures

  o  how the OriginatorInfo and RecipientInfo elements within a
     Signature Component are used to identify the Organisations
     associated with the signature

  o  how IOTP uses signatures to prove actions complete successfully

6.1.1 IOTP Signature Example

  An example of how signatures are used is illustrated in the figure
  below which shows how the various components and elements in a
  Baseline Purchase relate to one another. Refer to this example in the
  later description of how signatures are used to check a payment or
  delivery can occur (see section 6.3).

  Note: A Baseline Purchase transaction has been used for illustration
  purposes. The usage of the elements and attributes is the same for
  all types of IOTP Transactions.












Burdett                      Informational                     [Page 80]

RFC 2801                       IOTP/1.0                       April 2000


*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

TPO SELECTION BLOCK          TPO BLOCK           IOTPSIGNATURE BLOCK
                                                | (Offer Response)
Brand Selection             Organisation<---    |------Signature
  Component                 Component       |   |      Component
     |                       |              |           -Manifest
     |BrandList               -Trading Role |            |
     |  Ref                     Element     | Originator |-Orig.
     v                         (Merchant)    ------------|--Info
   Brand List                                    Ref     |
 >Component                                              |
| |-Protocol       ------>  Organisation     Recipient   |-Recipient
| | Amount Elem   |         Component <------------------|--Info
| |   |           |          |                 Refs      |
| |Pay|Protocol   |Action     -Trading Role              |
| |   | Ref       |OrgRef       Element                  |
| |   v           |          (Payment Handler)           |
|  -PayProtocol--                                        |
|    Elem                  ->Organisation    Recipient   |-Recipient
|                         |  Component <--------------------Info
|                         |  |                 Refs
|                         |   -Trading Role
|                         |     Element
|                         | (Delivery Handler
|
|           OFFER RESPONSE BLOCK
|                         |
|BrandListRef             |ActionOrgRef
|                         |
 --Payment                 ---Delivery
  Component                  Component

The Manifest element in the Signature Component contains digests of:
the Trans Ref Block (not shown); the Transaction ID Component (not
shown); Organisation Components (Merchant, Payment Handler, Delivery
Handler); the Brand List Component; the Order Component, the Payment
Component the Delivery Component and the Brand Selection Component (if a
Brand Dependent Purchase).

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

        Figure 11 Example use of Signatures for Baseline Purchase








Burdett                      Informational                     [Page 81]

RFC 2801                       IOTP/1.0                       April 2000


6.1.2 OriginatorInfo and RecipientInfo Elements

  The OriginatorRef attribute of the OriginatorInfo element in the
  Signature Component contains an Element Reference (see section 3.5)
  that points to the Organisation Component of the Organisation which
  generated the Signature. In this example its the Merchant.

  Note that the value of the content of the Attribute element with a
  Type attribute set to IOTP Signature Type must match the Trading Role
  of the Organisation which signed it. If it does not, then it is an
  error. Valid combinations are given in the table below.

        IOTP Signature Type    Valid Trading Role

        OfferResponse           Merchant

        PaymentResponse         PaymentHandler

        DeliveryResponse        DeliveryHandler

        AuthenticationRequest   any role

        AuthenticationResponse  any role

        PingRequest             any role

        PingResponse            any role

  The RecipientRefs attribute of the RecipientInfo element in the
  Signature Component contains Element References to the Organisation
  Components of the Organisations that should use the signature to
  verify that:

  o  they have a pre-existing relationship with the Organisation that
     generated the signature,

  o  the data which is secured by the signature has not been changed,

  o  the data has been signed correctly, and

  o  the action they are required to undertake on behalf of the
     Merchant is therefore authorised.

  Note that if symmetric cryptography is being used then a separate
  RecipientInfo and Value elements for each different set of shared
  secret keys are likely within the Signature Component.





Burdett                      Informational                     [Page 82]

RFC 2801                       IOTP/1.0                       April 2000


  Alternatively if asymmetric cryptography is being used then the
  RecpientRefs attribute of one RecipientInfo element may refer to
  multiple Organisation Components if they are all using the same
  certificates.

6.1.3 Using signatures to Prove Actions Complete Successfully

  Proving an action completed successfully, is achieved by signing data
  on Response messages. Specifically:

  o  on the Offer Response, when a Merchant is making an Offer to the
     Consumer which can then be sent to either:

     -  a Payment Handler to prove that the Merchant authorises
        Payment, or

     -  a Delivery Handler to prove that Merchant authorises Delivery,
        provided other necessary authorisations are complete (see
        below)

  o  on the Payment Response, when a Payment Handler is generating a
     Payment Receipt which can be sent to either:

     -  a Delivery Handler, in a Delivery Request Block to authorise
        Delivery together with the Offer Response signature, or

     -  another Payment Handler, in a second Payment Request, to
        authorise the second payment in a Value Exchange IOTP
        Transaction

  o  Delivery Response, when a Delivery Handler is generating a
     Delivery Note. This can be used to prove after the event what the
     Delivery Handler said they would do

  o  Authentication Response. One method of authenticating another
     party to a trade is to send an Authentication Request specifying
     that a Digital Signature should be used for authentication

  o  Transaction Status Inquiry. The Inquiry Response Block may be
     digitally signed to attest to the authenticity of the response

  o  Ping. The Ping Response may be digitally signed so that checks can
     be made that the signature can be understood.

  This proof of an action may, in future versions of IOTP, also be used
  to prove after the event that the IOTP transaction occurred. For
  example to a Customer Care Provider.




Burdett                      Informational                     [Page 83]

RFC 2801                       IOTP/1.0                       April 2000


6.2 Checking a Signature is Correctly Calculated

  Checking a signature is correctly calculated is part of checking for
  Message Level Errors (see section 4.3.2). It is included here so that
  all signature and security related considerations are kept together.

  Before a Trading Role can check a signature it must identify which of
  the potentially multiple Signature elements should be checked. The
  steps involved are as follows:

  o  check that a Signature Block is present and it contains one or
     more Signature Components

  o  identify the Organisation Component which contains an OrgId
     attribute for the Organisation which is carrying out the signature
     check. If no or more than one Organisation Component is found then
     it is an error

  o  use the ID attribute of the Organisation Component to find the
     RecipientInfo element that contains a RecipientRefs attribute that
     refers to that Organisation Component. Note there may be no
     signatures to verify

  o  check the Signature Component that contains the identified
     RecipientInfo element as follows:

     -  use the SignatureValueRef and the SignatureAlgorithmRef
        attributes to identify, respectively: the Value element that
        contains the signature to be checked and the Signature
        Algorithm element that describes the signature algorithm to be
        used to verify the Signature, then

     -  if the Signature Algorithm element indicates that asymmetric
        cryptography is being used then use the SignatureCertRef to
        identify the Certificate to be used by the signature algorithm

     -  if Signature Algorithm element indicates that symmetric
        cryptography is being used then the content of the
        RecipientInfo element is used to identify the correct shared
        secret key to use

     -  use the specified signature algorithm to check that the Value
        Element correctly signs the Manifest Element

     -  check that the Digest Elements in the Manifest Element are
        correctly calculated where Components or Blocks referenced by
        the Digest have been received by the Organisation checking the
        signature.



Burdett                      Informational                     [Page 84]

RFC 2801                       IOTP/1.0                       April 2000


6.3 Checking a Payment or Delivery can occur

  This section describes the processes required for a Payment Handler
  or Delivery Handler to check that a payment or delivery can occur.
  This may include checking signatures if this is specified by the
  Merchant.

  In outline the steps are:

  o  check that the Payment Request or Delivery Request has been sent
     to the correct Organisation

  o  check that correct IOTP components are present in the request, and

  o  check that the payment or delivery is authorised

  For clarity and brevity the following terms or phrases are used in
  this section:

  o  a "Request Block" is used to refer to either a Payment Request
     Block (see section 8.7) or a Delivery Request Block (see section
     8.10) unless specified to the contrary

  o  a "Response Block" is used to refer to either a Payment Response
     Block (see section 8.9) or a Delivery Response Block (see section
     8.11)

  o  an "Action" is used to refer to an action which occurs on receipt
     of a Request Block. Actions can be either a Payment or a Delivery

  o  an "Action Organisation", is used to refer to the Payment Handler
     or Delivery Handler that carries out an Action

  o  a "Signer of an Action", is used to refer to the Organisations
     that sign data about an Action to authorise the Action, either in
     whole or in part

  o  a "Verifier of an Action", is used to refer to the Organisations
     that verify data to determine if they are authorised to carry out
     the Action

  o  an ActionOrgRef attribute contains Element References which can be
     used to identify the "Action Organisation" that should carry out
     an Action







Burdett                      Informational                     [Page 85]

RFC 2801                       IOTP/1.0                       April 2000


6.3.1 Check Request Block sent Correct Organisation

  Checking the Request Block was sent to the correct Organisation
  varies depending on whether the request refers to a Payment or a
  Delivery.

6.3.1.1 Payment

  In outline a Payment Handler checks if it can accept or make a
  payment by identifying the Payment Component in the Payment Request
  Block it has received, then using the ID of the Payment Component to
  track through the Brand List and Brand Selection Components to
  identify the Organisation selected by the Consumer and then checking
  that this Organisation is itself.





































Burdett                      Informational                     [Page 86]

RFC 2801                       IOTP/1.0                       April 2000


  The way data is accessed to do this is illustrated in the figure
  below.

  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
                                                    Start
                                                     |
                                                     v
  Brand List<--------------------------+-----------Payment
  Component         BrandListRef       |          Component
   |                                   |
   |-Brand<--------------------------  |
   | Element        BrandRef         | |
   |  |                          Brand Selection
   |  |Protocol                     Component
   |  | AmountRefs                   | |
   |  v                  Protocol    | |
   |-Protocol Amount<----------------  |
   | Element----------  AmountRef      |
   |  |               |                |
   |  |Currency       |Pay             |
   |  | AmountRefs    |Protocol        |
   |  v               |Ref             |
   |-Currency Amount  |                |
   | Element<---------|----------------
   |                  |
    -PayProtocol<-----
     Element---------------------->Organisation
                    Action         Component
                    OrgRef          |
                                     -Trading Role
                                       Element
                                    (Payment Handler)

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

     Figure 12 Checking a Payment Handler can carry out a Payment

  The following describes the steps involved and the checks which need
  to be made:

  o  Identify the Payment Component (see section 7.9) in the Payment
     Request Block that was received.

  o  Identify the Brand List and Brand Selection Components for the
     Payment Component. This involves:






Burdett                      Informational                     [Page 87]

RFC 2801                       IOTP/1.0                       April 2000


     -  identifying the Brand List Component (see section 7.7) where
        the value of its ID attribute matches the BrandListRef
        attribute of the Payment Component. If no or more than one
        Brand List Component is found there is an error.

     -  identifying the Brand Selection Component (see section 7.8)
        where the value of its BrandListRef attribute matches the
        BrandListRef of the Payment Component. If no or more than one
        matching Brand Selection Component is found there is an error.

  o  Identify the Brand, Protocol Amount, Pay Protocol and Currency
     Amount elements within the Brand List that have been selected by
     the Consumer as follows:

     -  the Brand Element (see section 7.7.1) selected is the element
        where the value of its Id attribute matches the value of the
        BrandRef attribute in the Brand Selection. If no or more than
        one matching Brand Element is found then there is an error.

     -  the Protocol Amount Element (see section 7.7.3) selected is the
        element where the value of its Id attribute matches the value
        of the ProtocolAmountRef attribute in the Brand Selection
        Component. If no or more than one matching Protocol Amount
        Element is found there is an error

     -  the Pay Protocol Element (see section 7.7.5) selected is the
        element where the value of its Id attribute matches the value
        of the PayProtocolRef attribute in the identified Protocol
        Amount Element.  If no or more than one matching Pay Protocol
        Element is found there is an error

     -  the Currency Amount Element (see section 7.7.4) selected is the
        element where the value of its Id attribute matches the value
        of the CurrencyAmountRef attribute in the Brand Selection
        Component. If no or more than one matching Currency Amount
        element is found there is an error

  o  Check the consistency of the references in the Brand List and
     Brand Selection Components:

     -  check that an Element Reference exists in the
        ProtocolAmountRefs attribute of the identified Brand Element
        that matches the Id attribute of the identified Protocol Amount
        Element. If no or more than one matching Element Reference can
        be found there is an error






Burdett                      Informational                     [Page 88]

RFC 2801                       IOTP/1.0                       April 2000


     -  check that the CurrencyAmountRefs attribute of the identified
        Protocol Amount element contains an element reference that
        matches the Id attribute of the identified Currency Amount
        element. If no or more than one matching Element Reference is
        found there is an error.

     -  check the consistency of the elements in the Brand List.
        Specifically, the selected Brand, Protocol Amount, Pay Protocol
        and Currency Amount Elements are all child elements of the
        identified Brand List Component. If they are not there is an
        error.

  o  Check that the Payment Handler that received the Payment Request
     Block is the Payment Handler selected by the Consumer. This
     involves:

     -  identifying the Organisation Component for the Payment Handler.
        This is the Organisation Component where its ID attribute
        matches the ActionOrgRef attribute in the identified Pay
        Protocol Element. If no or more than one matching Organisation
        Component is found there is an error

     -  checking the Organisation Component has a Trading Role Element
        with a Role attribute of PaymentHandler. If not there is an
        error

     -  finally, if the identified Organisation Component is not the
        same as the Organisation that received the Payment Request
        Block, then there is an error.






















Burdett                      Informational                     [Page 89]

RFC 2801                       IOTP/1.0                       April 2000


6.3.1.2 Delivery

  The way data is accessed by a Delivery Handler in order to check that
  it may carry out a delivery is illustrated in the figure below.

  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
                           Start
                             |
                             v
                          Delivery
                          Component
                             |
                             |ActionOrgRef
                             |
                             v
                          Organisation
                          Component
                          |
                           -Trading Role
                             Element
                          (Delivery Handler)

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

        Figure 13 Checking a Delivery Handler can carry out a Delivery

  The steps involved are as follows:

  o  Identify the Delivery Component in the Delivery Request Block. If
     there is no or more than one matching Delivery Component there is
     an error

  o  Use the ActionOrgRef attribute of the Delivery Component to
     identify the Organisation Component of the Delivery Handler. If
     there is no or more than one matching Organisation Component there
     is an error

  o  If the Organisation Component for the Delivery Handler does not
     have a Trading Role Element with a Role attribute of
     DeliveryHandler there is an error

  o  Finally, if the Organisation that received the Delivery Request
     Block does not identify the Organisation Component for the
     Delivery Handler as itself, then there is an error.







Burdett                      Informational                     [Page 90]

RFC 2801                       IOTP/1.0                       April 2000


6.3.2 Check Correct Components present in Request Block

  Check that the correct components are present in the Payment Request
  Block (see section 8.7) or in the Delivery Request Block (see section
  8.10).

  If components are missing, there is an error.

6.3.3 Check an Action is Authorised

  The previous steps identified the Action Organisation and that all
  the necessary components are present. This step checks that the
  Action Organisation is authorised to carry out the Action.

  In outline the Action Organisation will identifies the Merchant,
  checks that it has a pre-existing agreement with the Merchant that
  allows it carry out the Action and that any constraints implied by
  that agreement are being followed, then, if signatures are required,
  it checks that they sign the correct data.

  The steps involved are as follows:

  o  Identify the Merchant. This is the Organisation Component with a
     Trading Role Element which has a Role attribute with a value of
     Merchant. If no or more than one Trading Role Element is found,
     there is an error

  o  Check the Action Organisation's agreements with the Merchant
     allows the Action to be carried out. To do this the Action
     Organisation must check that:

     -  the Merchant is known and a pre-existing agreement exists for
        the Action Organisation to be their agent for the payment or
        delivery

     -  they are allowed to take part in the type of IOTP transaction
        that is occurring. For example a Payment Handler may have
        agreed to accept payments as part of a Baseline Purchase, but
        not make payments as part of a Baseline Refund

     -  any constraints in their agreement with the Merchant are being
        followed, for example, whether or not an Offer Response
        signature is required

  o  Check the signatures are correct. If signatures are required then
     they need to be checked. This involves:





Burdett                      Informational                     [Page 91]

RFC 2801                       IOTP/1.0                       April 2000


     -  Identifying the correct signatures to check. This involves the
        Action Organisation identifying the Signature Components that
        contain references to the Action Organisation (see 6.3.1).
        Depending on the IOTP Transaction being carried out (see
        section 9) either one or two signatures may be identified

     -  checking that the Signature Components are correct. This
        involves checking that Digest elements exist within the
        Manifest Element that refer to the necessary Trading Components
        (see section 6.3.3.1).

6.3.3.1 Check the Signatures Digests are correct

  All Signature Components contained within IOTP Messages must include
  Digest elements that refer to:

  o  the Transaction Id Component (see section 3.3.1) of the IOTP
     message that contains the Signature Component. This binds the
     globally unique IotpTransId to other components which make up the
     IOTP Transaction

  o  the Transaction Reference Block (see section 3.3) of the first
     IOTP Message that contained the signature. This binds the
     IotpTransId with information about the IOTP Message contained
     inside the Message Id Component (see section 3.3.2).

  Check that each Signature Component contains Digest elements that
  refer to the correct data required.

  The Digest elements that need to be present depend on the Trading
  Role of the Organisation which generated (signed) the signature:

  o  if the signer of the signature is a Merchant then:

     -  Digest elements must be present for all the components in the
        Request Block apart from the Brand Selection Component which is
        optional

  o  if the signer of the signature is a Payment Handler then Digest
     elements must be present for:

     -  the Signature Component signed by the Merchant, and optionally

     -  one or more Signature Components signed by the previous Payment
        Handler(s) in the Transaction.






Burdett                      Informational                     [Page 92]

RFC 2801                       IOTP/1.0                       April 2000


7. Trading Components

  This section describes the Trading Components used within IOTP.
  Trading Components are the child XML elements which occur immediately
  below a Trading Block as illustrated in the diagram below.














































Burdett                      Informational                     [Page 93]

RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

            IOTP MESSAGE  <----------- IOTP Message - an XML Document
             |                         which is transported between the
             |                         Trading Roles
             |-Trans Ref Block <-----  Trans Ref Block - contains
             |  |                      information which describes the
             |  |                      IOTP Transaction and the IOTP
                                       Message.
   --------> |  |-Trans Id Comp. <---  Transaction Id Component -
  |          |  |                      uniquely identifies the IOTP
  |          |  |                      Transaction. The Trans Id
  |          |  |                      Components are the same across
  |          |  |                      all IOTP messages that comprise
  |          |  |                      a single IOTP transaction.
  |          |  |-Msg Id Comp. <-----  Message Id Component -
  |          |                         identifies and describes an IOTP
  |          |                         Message within an IOTP
  |          |                         Transaction
  |          |-Signature Block <-----  Signature Block (optional) -
  |          |  |                      contains one or more Signature
  |          |  |                      Components and their associated
  |          |  |                      Certificates
  |     ---> |  |-Signature Comp. <--  Signature Component - contains
  |    |     |  |                      digital signatures. Signatures
  |    |     |  |                      may sign digests of the Trans Ref
  |    |     |  |                      Block and any Trading Component
  |    |     |  |                      in any IOTP Message in the same
  |    |     |  |                      IOTP Transaction.
  |    |     |  |-Certificate Comp. <- Certificate Component. Used to
  |    |     |                         check the signature.
    Trading  |-Trading Block <-------- Trading Block - an XML Element
  Components |  |-Trading Comp.        within an IOTP Message that
  |    |     |  |-Trading Comp.        contains a predefined set of
  |     ---> |  |-Trading Comp.        Trading Components
  |          |  |-Trading Comp.
  |          |  |-Trading Comp. <----- Trading Components - XML
  |          |                         Elements within a Trading Block
  |          |-Trading Block           that contain a predefined set of
   --------> |  |-Trading Comp.        XML elements and attributes
             |  |-Trading Comp.        containing information required
             |  |-Trading Comp.        to support a Trading Exchange
             |  |-Trading Comp.
             |  |-Trading Comp.
  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                         Figure 14 Trading Components




Burdett                      Informational                     [Page 94]

RFC 2801                       IOTP/1.0                       April 2000


  The Trading Components described in this section are listed below in
  approximately the sequence they are likely to be used:

  o  Protocol Options Component

  o  Authentication Request Component

  o  Authentication Response Component

  o  Trading Role Information Request Component

  o  Order Component

  o  Organisation Component

  o  Brand List Component

  o  Brand Selection Component

  o  Payment Component

  o  Payment Scheme Component

  o  Payment Receipt Component

  o  Delivery Component

  o  Delivery Data Component

  o  Delivery Note Component

  o  Signature Component

  o  Certificate Component

  o  Error Component

  Note that the following components are listed in other sections of
  this specification:

  o  Transaction Id Component (see section 3.3.1)

  o  Message Id Component (see section 3.3.2)








Burdett                      Informational                     [Page 95]

RFC 2801                       IOTP/1.0                       April 2000


7.1 Protocol Options Component

  Protocol options are options which apply to the IOTP Transaction as a
  whole. Essentially it provides a short description of the entire
  transaction and the net location which the Consumer role should
  branch to if the IOTP Transaction is successful.

  The definition of a Protocol Options Component is as follows.

  <!ELEMENT ProtocolOptions EMPTY >
  <!ATTLIST ProtocolOptions
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   SenderNetLocn      CDATA   #IMPLIED
   SecureSenderNetLocn CDATA  #IMPLIED
   SuccessNetLocn     CDATA   #REQUIRED >

  Attributes:

  ID                   An identifier which uniquely identifies the
                       Protocol Options Component within the IOTP
                       Transaction.

  Xml:lang             Defines the language used by attributes or child
                       elements within this component, unless
                       overridden by an xml:lang attribute on a child
                       element. See section 3.8 Identifying Languages.

  ShortDesc            This contains a short description of the IOTP
                       Transaction in the language defined by xml:lang.
                       Its purpose is to provide an explanation of what
                       type of IOTP Transaction is being conducted by
                       the parties involved.

                       It is used to facilitate selecting an individual
                       transaction from a list of similar transactions,
                       for example from a database of IOTP transactions
                       which has been stored by a Consumer, Merchant,
                       etc.

  SenderNetLocn        This contains the non secured net location of
                       the sender of the TPO Block in which the
                       Protocol Options Component is contained.

                       It is the net location to which the recipient of
                       the TPO block should send a TPO Selection Block
                       if required.



Burdett                      Informational                     [Page 96]

RFC 2801                       IOTP/1.0                       April 2000


                       The content of this attribute is dependent on
                       the Transport Mechanism see the Transport
                       Mechanism Supplement.

  SecureSenderNetLocn  This contains the secured net location of the
                       sender of the TPO Block in which the Protocol
                       Options Component is contained.

                       The content of this attribute is dependent on
                       the Transport Mechanism see the Transport
                       Mechanism Supplement.

  SuccessNetLocn       This contains the net location that should be
                       displayed after the IOTP Transaction has
                       successfully completed.

                       The content of this attribute is dependent on
                       the Transport Mechanism see the Transport
                       Mechanism Supplement.

  Either SenderNetLocn, SecureSenderNetLocn or both must be present.

7.2 Authentication Request Component

  This Trading Component contains parameter data that is used in an
  Authentication of one Trading Role by another. Its definition is as
  follows.

  <!ELEMENT AuthReq (Algorithm, PackagedContent*)>
  <!ATTLIST AuthReq
   ID                 ID      #REQUIRED
   AuthenticationId   CDATA   #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  If required the Algorithm may use the challenge data, contained in
  the Packaged Content elements within the Authentication Request
  Component in its calculation. The format of the Packaged Contents are
  Algorithm dependent.

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Authentication Request Component within the IOTP
                     Transaction.

  AuthenticationId   An identifier specified by the Authenticator
                     which, if returned by the Organisation that
                     receives the Authentication Request, will enable



Burdett                      Informational                     [Page 97]

RFC 2801                       IOTP/1.0                       April 2000


                     the Authenticator to identify which Authentication
                     is being referred to.

  ContentSoftwareId  See section 14.Glossary

  Content:

  PackagedContent    This contains the challenge data as one or more
                     Packaged Content (see section 3.7) that is to be
                     responded to using the Algorithm defined by the
                     Algorithm element.

  Algorithm          This contains information which describes the
                     Algorithm (see 7.19 Signature Components) that
                     must be used to generate the Authentication
                     Response.

                     The Algorithms that may be used are identified by
                     the Name attribute of the Algorithm element. For
                     valid values see section 12. IANA Considerations.

7.3 Authentication Response Component

  The Authentication Response Component contains the results of an
  authentication request.  It uses the Algorithm contained in the
  Authentication Request Component (see section 7.2) selected from the
  Authentication Request Block (see section 8.4).

  Depending on the Algorithm selected, the results of applying the
  algorithm will either be contained in a Signature Component that
  signs both the Authentication Response and potentially other data, or
  in the Packaged Content elements within the Authentication Response
  Component.  Its definition is as follows.

  <!ELEMENT AuthResp (PackagedContent*) >
  <!ATTLIST AuthResp
   ID                 ID      #REQUIRED
   AuthenticationId   CDATA   #REQUIRED
   SelectedAlgorithmRef NMTOKEN #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                     An identifier which uniquely identifies the
                         Authentication Response Component within the
                         IOTP Transaction.





Burdett                      Informational                     [Page 98]

RFC 2801                       IOTP/1.0                       April 2000


  AuthenticationId       The Authentication identifier specified by the
                         Authenticator that was included in the
                         Authentication Request Component(see section
                         7.2). This will enable the Authenticator to
                         identify the Authentication that is being
                         referred to.

  SelectedAlgorithmRef   An Element Reference that identifies the
                         Algorithm element used to generate the
                         Authentication Response.

  ContentSoftwareId      See section 14.Glossary.

  Content:

  PackagedContent    This may contain the response generated as a
                     result of applying the Algorithm selected from the
                     Authentication Request Component see section 7.2.

                     For example, for a payment specific scheme, it may
                     contain scheme-specific data. Refer to the scheme-
                     specific supplemental documentation for
                     definitions of its content.

7.4 Trading Role Information Request Component

  This Trading Component contains a list of Trading Roles (see section
  2.1) about which information is being requested. The result of a
  Trading Role Request is a set of Organisation Components (see section
  7.6) that describe each of the Trading Roles requested.

  Example usage includes:

  o  a Merchant requesting that a Consumer provides Organisation
     Components for the Consumer and DelivTo Trading Roles

  o  a Consumer requesting from a Merchant, information about the
     Payment Handlers and Delivery Handlers that the Merchant uses.

  Its definition is as follows.

  <!ELEMENT TradingRoleInfoReq EMPTY>
  <!ATTLIST TradingRoleInfoReq
   ID                 ID      #REQUIRED
   TradingRoleList    NMTOKENS #REQUIRED >






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  Attributes:

  ID                 An identifier which uniquely identifies the
                     Trading Role Information Request Component within
                     the IOTP Transaction.

  TradingRoleList    Contains a list of one or more Trading Roles (see
                     the TradingRole attribute of the Trading Role
                     Element - section 7.6.2) for which information is
                     being requested.

7.5 Order Component

  An Order Component contains information about an order. Its
  definition is as follows.

  <!ELEMENT Order (PackagedContent*) >
  <!ATTLIST Order
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   OrderIdentifier    CDATA   #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   ApplicableLaw      CDATA   #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the Order
                     Component within the IOTP Transaction.

  xml:lang           Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.

  OrderIdentifier    This is a code, reference number or other
                     identifier which the creator of the Order may use
                     to identify the order. It must be unique within an
                     IOTP Transaction. If it is used in this way, then
                     it may remove the need to specify any content for
                     the Order element as the reference can be used to
                     look up the necessary information in a database.

  ShortDesc          A short description of the order in the language
                     defined by xml:lang. It is used to facilitate
                     selecting an individual order from a list of



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                     orders, for example from a database of orders
                     which has been stored by a Consumer, Merchant,
                     etc.

  OkFrom             The date and time in [UTC] format after which the
                     offer made by the Merchant lapses.

  OkTo               The date and time in [UTC] format before which a
                     Value Acquirer may accept the offer made by the
                     Merchant is not valid.

  ApplicableLaw      A phrase in the language defined by xml:lang which
                     describes the state or country of jurisdiction
                     which will apply in resolving problems or
                     disputes.

  ContentSoftwareId  See section 14.Glossary.

  Content:

  PackagedContent    An optional description of the order information
                     as one or more Packaged Contents (see section
                     3.7).

7.5.1 Order Description Content

  The Packaged Content element will normally be required, however it
  may be omitted where sufficient information about the purchase can be
  provided in the ShortDesc attribute. If the full Order Description
  requires it several Packaged Content elements may be used.

  Although the amount and currency are likely to appear in the Packaged
  Content of the Order Description it is the amount and currency
  contained in the payment related trading components (Brand List,
  Brand Selection and Payment) that is authoritative. This means it is
  important that the amount actually being paid (as contained in the
  payment related trading components) is prominently displayed to the
  Consumer.

  For interoperability, implementations must support Plain Text, HTML
  and XML as a minimum so that it can be easily displayed.

7.5.2 OkFrom and OkTo Timestamps

  Note that:

  o  the OkFrom date may be later than the OkFrom date on the Payment
     Component (see section 7.9) associated with this order, and



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  o  similarly, the OkTo date may be earlier that the OkTo date on the
     Payment Component (see section 7.9).

  Note: Disclaimer. The following information provided in this note
  does not represent formal advice of any of the authors of this
  specification. Readers of this specification must form their own
  views and seek their own legal counsel on the usefulness and
  applicability of this information.

  The merchant in the context of Internet commerce with anonymous
  consumers initially frames the terms of the offer on the web page,
  and in order to obtain the goods or services, the consumer must
  accept them.

  If there is to be a time-limited offer, it is recommended that
  merchants communicate this to the consumer and state in the order
  description in a manner which is clear to the consumer that:

  o  the offer is time limited

  o  the OkFrom and OkTo timestamps specify the validity of the offer

  o  the clock, e.g., the merchant's clock, that will be used to
     determine the validity of the offer

  Also note that although the OkFrom and OkTo dates are likely to
  appear in the Packaged Content of the Order Description it is the
  dates contained in the Order Component that is authoritative. This
  means it is important that the OkFrom and OkTo dates actually being
  used is prominently displayed to the Consumer.

7.6 Organisation Component

  The Organisation Component provides information about an individual
  or an Organisation. This can be used for a variety of purposes. For
  example:

  o to describe the merchant who is selling the goods,

  o to identify who made a purchase,

  o to identify who will take delivery of goods,

  o to provide a customer care contact,

  o to describe who will be the Payment Handler.





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  Note that the Organisation Components which must be present in an
  IOTP Message are dependent on the particular transaction being
  carried out.  Refer to section 9. Internet Open Trading Protocol
  Transactions, for more details.

  Its definition is as follows.

  <!ELEMENT Org (TradingRole+, ContactInfo?,
       PersonName?, PostalAddress?)>
  <!ATTLIST Org
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   OrgId              CDATA   #REQUIRED
   LegalName          CDATA   #IMPLIED
   ShortDesc          CDATA   #IMPLIED
   LogoNetLocn        CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Organisation Component within the IOTP
                     Transaction.

  xml:lang           Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.

  OrgId              A code which identifies the Organisation described
                     by the Organisation Component. See 7.6.1
                     Organisation IDs, below.

  LegalName          For Organisations which are companies this is
                     their legal name in the language defined by
                     xml:lang. It is required for Organisations who
                     have a Trading Role other than Consumer or
                     DelivTo.

  ShortDesc          A short description of the Organisation in the
                     language defined by xml:lang. It is typically the
                     name by which the Organisation is commonly known.
                     For example, if the legal name was "Blue Meadows
                     Financial Services Inc.". Then its short name
                     would likely be "Blue Meadows".

                     It is used to facilitate selecting an individual
                     Organisation from a list of Organisations, for
                     example from a database of Organisations involved



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                     in IOTP Transactions which has been stored by a
                     consumer.

  LogoNetLocn        The net location which can be used to download the
                     logo for the Organisation.

                     See section 10 Retrieving Logos.

                     The content of this attribute must conform to
                     [RFC1738].

  Content:

  TradingRole        See 7.6.2 Trading Role Element below.

  ContactInfo        See 7.6.3 Contact Information Element below.

  PersonName         See 7.6.4 Person Name below.

  PostalAddress      See 7.6.5 Postal Address below.

7.6.1 Organisation IDs

  Organisation IDs are used by one IOTP Trading Role to identify
  another.  In order to avoid confusion, this means that these IDs must
  be globally unique.

  In principle this is achieved in the following way:

  o  the Organisation Id for all trading roles, apart from the Consumer
     Trading Role, uses a domain name as their globally unique
     identifier,

  o  the Organisation Id for a Consumer Trading Role is allocated by
     one of the other Trading Roles in an IOTP Transaction and is made
     unique by concatenating it with that other roles' Organisation Id,

  o  once a Consumer is allocated an Organisation Id within an IOTP
     Transaction the same Organisation Id is used by all the other
     trading roles in that IOTP transaction to identify that Consumer.

  Specifically, the content of the Organisation ID is defined as
  follows:

  OrgId ::= NonConsumerOrgId | ConsumerOrgId
  NonConsumerOrgId ::= DomainName
  ConsumerOrgId ::= ConsumerOrgIdPrefix (namechar)+ "/" NonConsumerOrgId
  ConsumerOrgIdPrefix ::= "Consumer:"



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  ConsumerOrgId      The Organisation ID for a Consumer consists of:
                      o a standard prefix to identify that the
                        Organisation Id is for a consumer, followed by

                      o one or more characters which conform to the
                        definition of an XML "namechar". See [XML]
                        specifications, followed by
                      o the NonConsumerOrgId for the Organisation
                        which allocated the ConsumerOrgId. It is
                        normally the Merchant role.

                     Use of upper and lower case is not significant.

  NonConsumerOrgId   If the Role is not Consumer then this contains the
                     Canonical Name for the non-consumer Organisation
                     being described by the Organisation Component. See
                     [DNS] optionally followed by additional
                     characters, if required, to make the
                     NonConsumerOrgId unique.

                     Note that a NonConsumerOrgId may not start with
                     the ConsumerOrgIdPrefix.

                     Use of upper and lower case is not significant.

  Examples of Organisation Ids follow:

  o  newjerseybooks.com - a merchant Organisation id

  o  westernbank.co.uk - a Payment Handler Organisation id

  o  consumer:1000247ABH/newjerseybooks.com - a consumer Organisation
     id allocated by a merchant

7.6.2 Trading Role Element

  This identifies the Trading Role of an individual or Organisation in
  the IOTP Transaction. Note, an Organisation may have more than one
  Trading Role and several roles may be present in one Organisation
  element. Its definition is as follows:

  <!ELEMENT TradingRole EMPTY >
  <!ATTLIST TradingRole
   ID                 ID      #REQUIRED
   TradingRole        NMTOKEN #REQUIRED
   IotpMsgIdPrefix    NMTOKEN #REQUIRED
   CancelNetLocn      CDATA   #IMPLIED
   ErrorNetLocn       CDATA   #IMPLIED



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   ErrorLogNetLocn    CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Trading Role Element within the IOTP Transaction.

  TradingRole        The trading role of the Organisation. Valid values
                     are:
                      o Consumer. The person or Organisation that is
                        acting in the role of a consumer in the IOTP
                        Transaction.
                      o Merchant. The person or Organisation that is
                        acting in the role of merchant in the IOTP
                        Transaction.
                      o PaymentHandler. The financial institution or
                        other Organisation which is a Payment Handler
                        for the IOTP Transaction
                      o DeliveryHandler. The person or Organisation
                        that is the delivering the goods or services
                        for the IOTP Transaction
                      o DelivTo. The person or Organisation that is
                        receiving the delivery of goods or services in
                        the IOTP Transaction
                      o CustCare. The Organisation and/or individual
                        who will provide customer care for an IOTP
                        Transaction.

                     Values of TradingRole are controlled under the
                     procedures defined in section 12 IANA
                     Considerations which also allows user defined
                     values to be defined.

  IotpMsgIdPrefix    Contains the prefix which must be used for all
                     IOTP Messages sent by the Trading Role in this
                     IOTP Transaction. The values to be used are
                     defined in 3.4.1 IOTP Message ID Attribute
                     Definition.

  CancelNetLocn      This contains the net location of where the
                     Consumer should go to if the Consumer cancels the
                     transaction for some reason. It can be used by the
                     Trading Role to provide a response which is more
                     tailored to the circumstances of a particular
                     transaction.






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                     This attribute:
                      o must not be present when TradingRole is set to
                        Consumer role or DelivTo,

                      o must be present when TradingRole is set to
                        Merchant, PaymentHandler or DeliveryHandler.

                     The content of this attribute is dependent on the
                     Transport Mechanism see the Transport Mechanism
                     Supplement.

  ErrorNetLocn       This contains the net location that should be
                     displayed by the Consumer after the Consumer has
                     either received or generated an Error Block
                     containing an Error Component with the Severity
                     attribute set to either:
                      o HardError,
                      o Warning but the Consumer decides to not
                        continue with the transaction
                      o TransientError and the transaction has
                        subsequently timed out.

                     See section 7.21.1 Error Processing Guidelines for
                     more details.

                     This attribute:
                      o must not be present when TradingRole is set to
                        Consumer or DelivTo,
                      o must be present when TradingRole is set to
                        Merchant, PaymentHandler or DeliveryHandler.

                     The content of this attribute is dependent on the
                     Transport Mechanism see the Transport Mechanism
                     Supplement.

  ErrorLogNetLocn    Optional. This contains the net location that
                     Consumers should send IOTP Messages that contain
                     Error Blocks with an Error Component with the
                     Severity attribute set to either:
                      o HardError,
                      o Warning but the Consumer decides to not
                        continue with the transaction
                      o TransientError and the transaction has
                        subsequently timed out.

                     This attribute:
                      o must not be present when TradingRole is set to
                        Consumer role,



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                      o must be present when TradingRole is set to
                        Merchant, PaymentHandler or DeliveryHandler.

                     The content of this attribute is dependent on the
                     Transport Mechanism see the Transport Mechanism
                     Supplement.

                     The ErrorLogNetLocn can be used to send error
                     messages to the software company or some other
                     Organisation responsible for fixing problems in
                     the software which sent the incoming message. See
                     section 7.21.1 Error Processing Guidelines for
                     more details.

7.6.3 Contact Information Element

  This contains information which can be used to contact an
  Organisation or an individual. All attributes are optional however at
  least one item of contact information should be present. Its
  definition is as follows.

  <!ELEMENT ContactInfo EMPTY >
  <!ATTLIST ContactInfo
   xml:lang           NMTOKEN #IMPLIED
   Tel                CDATA   #IMPLIED
   Fax                CDATA   #IMPLIED
   Email              CDATA   #IMPLIED
   NetLocn            CDATA   #IMPLIED >

  Attributes:

  xml:lang           Defines the language used by attributes within
                     this element. See section 3.8 Identifying
                     Languages.

  Tel                A telephone number by which the Organisation may
                     be contacted. Note that this is a text field and
                     no validation is carried out on it.

  Fax                A fax number by which the Organisation may be
                     contacted. Note that this is a text field and no
                     validation is carried out on it.

  Email              An email address by which the Organisation may be
                     contacted. Note that this field should conform to
                     the conventions for address specifications
                     contained in [RFC822].




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  NetLocn            A location on the Internet by which information
                     about the Organisation may be obtained that can be
                     displayed using a web browser.

                     The content of this attribute must conform to
                     [RFC1738].

7.6.4 Person Name Element

  This contains the name of an individual person. All fields are
  optional however as a minimum either the GivenName or the FamilyName
  should be present. Its definition is as follows.

  <!ELEMENT PersonName EMPTY >
  <!ATTLIST PersonName
   xml:lang           NMTOKEN #IMPLIED
   Title              CDATA   #IMPLIED
   GivenName          CDATA   #IMPLIED
   Initials           CDATA   #IMPLIED
   FamilyName         CDATA   #IMPLIED >

  Attributes:

  xml:lang           Defines the language used by attributes within
                     this element. See section 3.8 Identifying
                     Languages.

  Title              A distinctive name; personal appellation,
                     hereditary or not, denoting or implying office
                     (e.g., judge, mayor) or nobility (e.g., duke,
                     duchess, earl), or used in addressing or referring
                     to a person (e.g., Mr, Mrs, Miss)

  GivenName          The primary or main name by which a person is
                     known amongst and identified by their family,
                     friends and acquaintances. Otherwise known as
                     first name or Christian Name.

  Initials           The first letter of the secondary names (other
                     than the Given Name) by which a person is known
                     amongst or identified by their family, friends and
                     acquaintances.

  FamilyName         The name by which family of related individuals
                     are known. It is typically the part of an
                     individual's name which is passed on by parents to
                     their children.




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7.6.5 Postal Address Element

  This contains an address which can be used, for example, for the
  physical delivery of goods, services or letters. Its definition is as
  follows.

  <!ELEMENT PostalAddress EMPTY >
  <!ATTLIST PostalAddress
   xml:lang           NMTOKEN #IMPLIED
   AddressLine1       CDATA   #IMPLIED
   AddressLine2       CDATA   #IMPLIED
   CityOrTown         CDATA   #IMPLIED
   StateOrRegion      CDATA   #IMPLIED
   PostalCode         CDATA   #IMPLIED
   Country            CDATA   #IMPLIED
   LegalLocation (True | False) 'False' >

  Attributes:

  xml:lang           Defines the language used by attributes within
                     this element. See section 3.8 Identifying
                     Languages.

  AddressLine1       The first line of a postal address. e.g., "The
                     Meadows"

  AddressLine2       The second line of a postal address. e.g., "Sandy
                     Lane"

  CityOrTown         The city of town of the address. e.g., "Carpham"

  StateOrRegion      The state or region within a country where the
                     city or town is placed. e.g., "Surrey"

  PostalCode        The code known as, for example a post code or zip
                     code, that is typically used by Postal
                     Organisations to organise postal deliveries into
                     efficient sequences. e.g., "KT22 1AA"

  Country            The country for the address. e.g., "UK"

  LegalLocation      This identifies whether the address is the
                     Registered Address for the Organisation. At least
                     one address for the Organisation must have a value
                     set to True unless the Trading Role is either
                     Consumer or DeliverTo.





Burdett                      Informational                    [Page 110]

RFC 2801                       IOTP/1.0                       April 2000


7.7 Brand List Component

  Brand List Components are contained within the Trading Protocol
  Options Block (see section 8.1) of the IOTP Transaction. They
  contains lists of:

  o  payment Brands (see also section 11.1 Brand Definitions and Brand
     Selection),

  o  amounts to be paid in the currencies that are accepted or offered
     by the Merchant,

  o  the payment protocols which can be used to make payments with a
     Brand, and

  o  the net locations of the Payment Handlers which accept payment for
     a payment protocol

  The definition of a Brand List Component is as follows.

  <!ELEMENT BrandList (Brand+, ProtocolAmount+,
   CurrencyAmount+, PayProtocol+) >
  <!ATTLIST BrandList
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   PayDirection (Debit | Credit) #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the Brand
                     List Component within the IOTP Transaction.

  xml:lang           Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.

  ShortDesc          A text description in the language defined by
                     xml:Lang giving details of the purpose of the
                     Brand List.  This information must be displayed to
                     the receiver of the Brand List in order to assist
                     with making the selection. It is of particular
                     benefit in allowing a Consumer to distinguish the
                     purpose of a Brand List when an IOTP Transaction
                     involves more than one payment.





Burdett                      Informational                    [Page 111]

RFC 2801                       IOTP/1.0                       April 2000


  PayDirection       Indicates the direction in which the payment for
                     which a Brand is being selected is to be made. Its
                     values may be:
                      o Debit The sender of the Payment Request Block
                        (e.g., the Consumer) to which this Brand List
                        relates will make the payment to the Payment
                        Handler, or
                      o Credit The sender of the Payment Request Block
                        to which this Brand List relates will receive a
                        payment from the Payment Handler.

  Content:

  Brand              This describes a Brand. The sequence of the Brand
                     elements (see section 7.7.1) within the Brand List
                     does not indicate any preference. It is
                     recommended that software which processes this
                     Brand List presents Brands in a sequence which the
                     receiver of the Brand List prefers.

  ProtocolAmount     This links a particular Brand to:
                      o the currencies and amounts in CurrencyAmount
                        elements that can be used with the Brand, and
                      o the Payment Protocols and Payment Handlers,
                        which can be used with those currencies and
                        amounts, and a particular Brand

  CurrencyAmount     This contains a currency code and an amount.

  PayProtocol        This contains information about a Payment Protocol
                     and the Payment Handler which may be used with a
                     particular Brand.

  The relationships between the elements which make up the content of
  the Brand List is illustrated in the diagram below.
















Burdett                      Informational                    [Page 112]

RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

                   Brand List Component

                     |                   ProtocolAmountRefs
                     |-Brand Element-----------------------------
                     |  |                                        |
                     |   - Protocol Brand Element--------        |
                     |                                   |       |
                     |                         ProtocolId|       |
                     |                                   |       |
                     |-Protocol Amount Element<----------+-------
                     |  |                      |         |
                     |  |                      |         |
                     |  |CurrencyAmountRefs    |Pay      |
                     |  |                      |Protocol |
                     |  v                      |Ref      |
                     |-Currency Amount Element |         |
                     | Element                 |         |
                     |                         |         |
                      -PayProtocolElement<------<--------

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                  Figure 15 Brand List Element Relationships

  Examples of complete Brand Lists are contained in section 11.2 Brand
  List Examples.

7.7.1 Brand Element

  A Brand Element describes a brand that can be used for making a
  payment.  One or more of these elements is carried in each Brand List
  Component that has the PayDirection attribute set to Debit.  Exactly
  one Brand Element may be carried in a Brand List Component that has
  the PayDirection attribute set to Credit.

  <!ELEMENT Brand (ProtocolBrand*, PackagedContent*) >
  <!ATTLIST Brand
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #IMPLIED
   BrandId            CDATA   #REQUIRED
   BrandName          CDATA   #REQUIRED
   BrandLogoNetLocn   CDATA   #REQUIRED
   BrandNarrative     CDATA   #IMPLIED
   ProtocolAmountRefs IDREFS  #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >




Burdett                      Informational                    [Page 113]

RFC 2801                       IOTP/1.0                       April 2000


  Attributes:

  ID                  Element identifier, potentially referenced in a
                      Brand Selection Component contained in a later
                      Payment Request message and uniquely identifies
                      the Brand element within the IOTP Transaction.

  xml:lang            Defines the language used by attributes and
                      content of this element. See section 3.8
                      Identifying Languages.

  BrandId             This contains a unique identifier for the brand
                      (or promotional brand). It is used to match
                      against a list of Payment Instruments which the
                      Consumer holds to determine whether or not the
                      Consumer can pay using the Brand.

                      Values of BrandId are managed under the procedure
                      described in section 12 IANA Considerations.

                      As values of BrandId are controlled under the
                      procedures defined in section 12 IANA
                      Considerations user defined values may be
                      defined.

  BrandName           This contains the name of the brand, for example
                      MasterCard Credit. This is the description of the
                      Brand which is displayed to the consumer in the
                      Consumers language defined by xml:lang. For
                      example it might be "American Airlines Advantage
                      Visa". Note that this attribute is not used for
                      matching against the payment instruments held by
                      the Consumer.

  BrandLogoNetLocn    The net location which can be used to download
                      the logo for the Organisation. See section
                      Retrieving Logos (see section 10).

                      The content of this attribute must conform to
                      [RFC1738].

  BrandNarrative      This optional attribute is designed to be used by
                      the Merchant to indicate some special conditions
                      or benefit which would apply if the Consumer
                      selected that brand. For example "5% discount",
                      "free shipping and handling", "free breakage
                      insurance for 1 year", "double air miles apply",
                      etc.



Burdett                      Informational                    [Page 114]

RFC 2801                       IOTP/1.0                       April 2000


  ProtocolAmountRefs  Identifies the protocols and related currencies
                      and amounts which can be used with this Brand.
                      Specified as a list of ID's of Protocol Amount
                      Elements (see section 7.7.3) contained within the
                      Brand List.

  ContentSoftwareId   See section 14.Glossary.

  Content:

  ProtocolBrand      Protocol Brand elements contain brand information
                     to be used with a specific payment protocol (see
                     section 7.7.2)


  PackagedContent    Optional Packaged Content (see section 3.7)
                     elements containing information about the brand
                     which may be used by the payment protocol. The
                     content of this information is defined in the
                     supplement for a payment protocol which describes
                     how the payment protocol works with IOTP.

  Example Brand Elements are contained in section 11.2 Brand List
  Examples.

7.7.2 Protocol Brand Element

  The Protocol Brand Element contains information that is specific to
  the use of a particular Protocol with a Brand. Its definition is as
  follows.

  <!ELEMENT ProtocolBrand (PackagedContent*) >
  <!ATTLIST ProtocolBrand
   ProtocolId         CDATA   #REQUIRED
   ProtocolBrandId    CDATA   #REQUIRED >


  Attributes:

  ProtocolId         This must match the value of a ProtocolId
                     attribute in a Pay Protocol Element (see section
                     7.7.5).

                     The values of ProtocolId should be unique within a
                     Brand Element otherwise there is an error.






Burdett                      Informational                    [Page 115]

RFC 2801                       IOTP/1.0                       April 2000


  ProtocolBrandId    This is the Payment Brand Id to be used with a
                     particular payment protocol. For example, SET and
                     EMV have their own well defined, yet different,
                     values for the Brand Id to be used with each
                     protocol.

                     The valid values of this attribute are defined in
                     the supplement for the payment protocol identified
                     by ProtocolId that describes how the payment
                     protocol works with IOTP.

  Content:

  PackagedContent    Optional Packaged Content (see section 3.7)
                     elements containing information about the
                     protocol/brand which may be used by the payment
                     protocol. The content of this information is
                     defined in the supplement for a payment protocol
                     which describes how the payment protocol works
                     with IOTP.

7.7.3 Protocol Amount Element

  The Protocol Amount element links a Brand to:

  o  the currencies and amounts in Currency Amount Elements (see
     section 7.7.4) that can be used with the Brand, and

  o  the Payment Protocols and Payment Handlers defined in a Pay
     Protocol Element (see section 7.7.5), which can be used with those
     currencies and amounts.

  Its definition is as follows:

  <!ELEMENT ProtocolAmount (PackagedContent*) >
  <!ATTLIST ProtocolAmount
   ID                 ID      #REQUIRED
   PayProtocolRef     IDREF   #REQUIRED
   CurrencyAmountRefs IDREFS  #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                  Element identifier, potentially referenced in a
                      Brand element; or in a Brand Selection Component
                      contained in a later Payment Request message
                      which uniquely identifies the Protocol Amount
                      element within the IOTP Transaction.



Burdett                      Informational                    [Page 116]

RFC 2801                       IOTP/1.0                       April 2000


  PayProtocolRef      Contains an Element Reference (see section 3.5)
                      that refers to the Pay Protocol Element (see
                      section 7.7.5) that contains the Payment Protocol
                      and Payment Handlers that can be used with the
                      Brand.

  CurrencyAmountRefs  Contains a list of  Element References (see
                      section 3.5) that refer to the Currency Amount
                      Element (see section 7.7.4) that describes the
                      currencies and amounts that can be used with the
                      Brand.

  ContentSoftwareId   See section 14. Glossary.

  Content:

  PackagedContent    Optional Packaged Content (see section 3.7)
                     elements containing information about the protocol
                     amount which may be used by the payment protocol.
                     The content of this information is defined in the
                     supplement for a payment protocol which describes
                     how the payment protocol works with IOTP.

  Examples of Protocol Amount Elements are contained in section 11.2
  Brand List Examples.

7.7.4 Currency Amount Element

  A Currency Amount element contains:

  o a currency code (and its type), and

  o an amount.

  One or more of these elements is carried in each Brand List
  Component.  Its definition is as follows:

  <!ELEMENT CurrencyAmount EMPTY >
  <!ATTLIST CurrencyAmount
   ID                 ID      #REQUIRED
   Amount             CDATA   #REQUIRED
   CurrCodeType       NMTOKEN 'ISO4217-A'
   CurrCode           CDATA   #REQUIRED >

  Attributes:

  ID                 Element identifier, potentially referenced in a
                     Brand element; or in a Brand Selection Component



Burdett                      Informational                    [Page 117]

RFC 2801                       IOTP/1.0                       April 2000


                     contained in a later Payment Request message which
                     uniquely identifies the Currency Amount Element
                     within the IOTP Transaction.

  Amount             Indicates the amount to be paid in whole and
                     fractional units of the currency. For example
                     $245.35 would be expressed "245.35". Note that
                     values smaller than the smallest denomination are
                     allowed. For example one tenth of a cent would be
                     "0.001".

  CurrCodeType       Indicates the domain of the CurrCode. This
                     attribute is included so that the currency code
                     may support non-standard "currencies" such as
                     frequent flyer points, trading stamps, etc. Its
                     values may be:
                      o ISO4217-A (the default) indicates the currency
                        code is a three character alphabetic currency
                        code that conforms to [ISO 4217]
                      o IOTP indicates that values of CurrCode are
                        managed under the procedure described in
                        section 12 IANA Considerations

  CurrCode           A code which identifies the currency to be used in
                     the payment. The domain of valid currency codes is
                     defined by CurrCodeType

                     As values of CurrCodeType are managed under the
                     procedure described in section 12 IANA
                     Considerations user defined values of CurrCodeType
                     may be defined.

  Examples of Currency Amount Elements are contained in section 11.2
  Brand List Examples.

7.7.5 Pay Protocol Element

  A Pay Protocol element specifies details of a Payment Protocol and
  the Payment Handler that can be used with a Brand. One or more of
  these elements is carried in each Brand List.

  <!ELEMENT PayProtocol (PackagedContent*) >
  <!ATTLIST PayProtocol
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #IMPLIED
   ProtocolId         NMTOKEN #REQUIRED
   ProtocolName       CDATA   #REQUIRED
   ActionOrgRef       NMTOKEN #REQUIRED



Burdett                      Informational                    [Page 118]

RFC 2801                       IOTP/1.0                       April 2000


   PayReqNetLocn      CDATA   #IMPLIED
   SecPayReqNetLocn   CDATA   #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                 Element identifier, potentially referenced in a
                     Brand element; or in a Brand Selection Component
                     contained in a later Payment Request message which
                     uniquely identifies the Pay Protocol element
                     within the IOTP Transaction.

  xml:lang           Defines the language used by attributes and
                     content of this element. See section 3.8
                     Identifying Languages.

  ProtocolId         Consists of a protocol name and version. For
                     example "SETv1.0".

                     The values of ProtocolId are defined by the
                     payment scheme/method owners in the document that
                     describes how to encapsulate a payment protocol
                     within IOTP.

  ProtocolName       A narrative description of the payment protocol
                     and its version in the language identified by
                     xml:lang. For example "Secure Electronic
                     Transaction Version 1.0". Its purpose is to help
                     provide information on the payment protocol being
                     used if problems arise.

  ActionOrgRef       An Element Reference (see section 3.5) to the
                     Organisation Component for the Payment Handler for
                     the Payment Protocol.

  PayReqNetLocn      The Net Location indicating where an unsecured
                     Payment Request message should be sent if this
                     protocol choice is used.

                     The content of this attribute is dependent on the
                     Transport Mechanism (such must conform to
                     [RFC1738].

  SecPayReqNetLocn   The Net Location indicating where a secured
                     Payment Request message should be sent if this
                     protocol choice is used.





Burdett                      Informational                    [Page 119]

RFC 2801                       IOTP/1.0                       April 2000


                     A secured payment involves the use of a secure
                     channel such as [SSL/TLS] in order to communicate
                     with the Payment Handler.

                     The content of this attribute must conform to
                     [RFC1738]. See also See section 3.9 Secure and
                     Insecure Net Locations.

  ContentSoftwareId  See section 14. Glossary.

  Content:

  PackagedContent    Optional Packaged Content elements (see section
                     3.7) containing information about the protocol
                     which is used by the payment protocol. The content
                     of this information is defined in the supplement
                     for a payment protocol which describes how the
                     payment protocol works with IOTP. An example of
                     its use could be to include a payment protocol
                     message.

  Examples of Pay Protocol Elements are contained in section 11.2 Brand
  List Examples.

7.8 Brand Selection Component

  A Brand Selection Component identifies the choice of payment brand,
  payment protocol and the Payment Handler.  This element is used:

  o  in Payment Request messages within Baseline Purchase and Baseline
     Value Exchange IOTP Transactions to identify the brand, protocol
     and payment handler for a payment, or

  o  to, optionally, inform a merchant in a purchase of the payment
     brand being used so that the offer and order details can be
     amended accordingly.

  In Baseline IOTP, the integrity of Brand Selection Components is not
  guaranteed.  However, modification of Brand Selection Components can
  only cause denial of service if the payment protocol itself is secure
  against message modification, duplication, and swapping attacks.

  The definition of a Brand Selection Component is as follows.

  <!ELEMENT BrandSelection (BrandSelBrandInfo?,
       BrandSelProtocolAmountInfo?,
       BrandSelCurrencyAmountInfo?) >
  <!ATTLIST BrandSelection



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RFC 2801                       IOTP/1.0                       April 2000


   ID                 ID      #REQUIRED
   BrandListRef       NMTOKEN #REQUIRED
   BrandRef           NMTOKEN #REQUIRED
   ProtocolAmountRef  NMTOKEN #REQUIRED
   CurrencyAmountRef  NMTOKEN #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the Brand
                     Selection Component within the IOTP Transaction.

  BrandListRef       The Element Reference (see section 3.5) of the
                     Brand List Component from which a Brand is being
                     selected

  BrandRef           The Element Reference of a Brand element within
                     the Brand List Component that is being selected
                     that is to be used in the payment.

  ProtocolAmountRef  The Element Reference of a Protocol Amount element
                     within the Brand List Component which is to be
                     used when making the payment.

  CurrencyAmountRef  The Element Reference of a Currency Amount element
                     within the Brand List Component which is to be
                     used when making the payment.

  Content:

  BrandSelBrandInfo,           This contains any additional data that
  BrandSelProtocolAmountInfo,  may be required by a particular payment
  BrandSelCurrencyAmountInfo   brand or protocol. See sections 7.8.1,
                                7.8.2, and 7.8.3.

  The following rules apply:

  o  the BrandListRef must contain the ID of a Brand List Component in
     the same IOTP Transaction

  o  every Brand List Component in the Trading Protocol Options Block
     (see section 8.1) must be referenced by one and only one Brand
     Selection Component

  o  the BrandRef must refer to the ID of a Brand contained within the
     Brand List Component referred to by BrandListRef






Burdett                      Informational                    [Page 121]

RFC 2801                       IOTP/1.0                       April 2000


  o  the ProtocolAmountRef must refer to one of the Element IDs listed
     in the ProtocolAmountRefs attribute of the Brand element
     identified by BrandRef

  o  the CurrencyAmountRef must refer to one of the Element IDs listed
     in the CurrencyAmountRefs attribute of the Protocol Amount Element
     identified by ProtocolAmountRef.

  An example of a Brand Selection Component is included in 11.2 Brand
  List Examples.

7.8.1 Brand Selection Brand Info Element

  The Brand Selection Brand Info Element contains any additional data
  that may be required by a particular payment brand. See the IOTP
  payment method supplement for a description of how and when it used.

  <!ELEMENT BrandSelBrandInfo (PackagedContent+) >
  <!ATTLIST BrandSelBrandInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ContentSoftwareId  See section 14. Glossary.

  Content:

  PackagedContent    Packaged Content elements (see section 3.7) that
                     contain additional data that may be required by a
                     particular payment brand. See the payment method
                     supplement for IOTP for rules on how this is used.

7.8.2 Brand Selection Protocol Amount Info Element

  The Brand Selection Protocol Amount Info Element contains any
  additional data that is payment protocol specific that may be
  required by a particular payment brand or payment protocol. See the
  IOTP payment method supplement for a description of how and when it
  used.

  <!ELEMENT BrandSelProtocolAmountInfo (PackagedContent+) >
  <!ATTLIST BrandSelProtocolAmountInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >






Burdett                      Informational                    [Page 122]

RFC 2801                       IOTP/1.0                       April 2000


  Attributes:

  ContentSoftwareId  See section 14. Glossary.

  Content:

  PackagedContent    Packaged Content elements (see section 3.7) that
                     may contain additional data that may be required
                     by a particular payment brand. See the payment
                     method supplement for IOTP for rules on how this
                     is used.

7.8.3 Brand Selection Currency Amount Info Element

  The Brand Selection Currency Amount Info Element contains any
  additional data that is payment brand and currency specific that may
  be required by a particular payment brand. See the IOTP payment
  method supplement for a description of how and when it used.

  <!ELEMENT BrandSelCurrencyAmountInfo (PackagedContent+) >
  <!ATTLIST BrandSelCurrencyAmountInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ContentSoftwareId  See section 14. Glossary.

  Content:

  PackagedContent    Packaged Content elements (see section 3.7) that
                     contain additional data relating to the payment
                     brand and currency. See the payment method
                     supplement for IOTP for rules on how this is used.

7.9 Payment Component

  A Payment Component contains information used to control how a
  payment is carried out. Its provides information on:

  o  the times within which a Payment with a Payment Handler may be
     started

  o  a reference to the Brand List (see section 7.7) which identifies
     the Brands, protocols, currencies and amounts which can be used to
     make a payment

  o  whether or not a payment receipt will be provided



Burdett                      Informational                    [Page 123]

RFC 2801                       IOTP/1.0                       April 2000


  o  whether another payment precedes this payment.

  Its definition is as follows.

  <!ELEMENT Payment EMPTY >
  <!ATTLIST Payment
   ID                 ID      #REQUIRED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   BrandListRef       NMTOKEN #REQUIRED
   SignedPayReceipt (True | False) #REQUIRED
   StartAfterRefs     NMTOKENS #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Payment Component within the IOTP Transaction.

  OkFrom             The date and time in [UTC] format after which a
                     Payment Handler may accept for processing a
                     Payment Request Block (see section 8.7) containing
                     the Payment Component.

  OkTo               The date and time in [UTC] format before which a
                     Payment Handler may accept for processing a
                     Payment Request Block containing the Payment
                     Component.

  BrandListRef       An Element Reference (see section 3.5) of a Brand
                     List Component (see section 7.7) within the TPO
                     Trading Block for the IOTP Transaction. The Brand
                     List identifies the alternative ways in which the
                     payment can be made.

  SignedPayReceipt   Indicates whether or not the Payment Response
                     Block (see section 8.9) generated by the Payment
                     Handler for the payment must be digitally signed.

  StartAfter         Contains Element References (see section 3.5) of
                     other Payment Components which describe payments
                     which must be complete before this payment can
                     start. If no StartAfter attribute is present then
                     there are no dependencies and the payment can
                     start immediately







Burdett                      Informational                    [Page 124]

RFC 2801                       IOTP/1.0                       April 2000


7.10 Payment Scheme Component

  A Payment Scheme Component contains payment protocol information for
  a specific payment scheme which is transferred between the parties
  involved in a payment for example a [SET] message. Its definition is
  as follows.

  <!ELEMENT PaySchemeData (PackagedContent+) >
  <!ATTLIST PaySchemeData
   ID                 ID      #REQUIRED
   PaymentRef         NMTOKEN #IMPLIED
   ConsumerPaymentId  CDATA   #IMPLIED
   PaymentHandlerPayId CDATA  #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                   An identifier which uniquely identifies the
                       Payment Scheme Component within the IOTP
                       Transaction.

  PaymentRef           An Element Reference (see section 3.5) to the
                       Payment Component (see section 7.9) to which
                       this Payment Scheme Component relates. It is
                       required unless the Payment Scheme Component is
                       part of an Transaction Inquiry Status
                       Transaction (see section 9.2.1).

  ConsumerPaymentId    An identifier specified by the Consumer which,
                       if returned by the Payment Handler in another
                       Payment Scheme Component or by other means, will
                       enable the Consumer to identify which payment is
                       being referred to.

  PaymentHandlerPayId  An identifier specified by the Payment Handler
                       which, if returned by the Consumer in another
                       Payment Scheme Component, or by other means,
                       will enable the Payment Handler to identify
                       which payment is being referred to. It is
                       required on every Payment Scheme Component apart
                       from the one contained in a Payment Request
                       Block.

  ContentSoftwareId    See section 14. Glossary.







Burdett                      Informational                    [Page 125]

RFC 2801                       IOTP/1.0                       April 2000


  Content:

  PackagedContent    Contains payment scheme protocol information as
                     Packaged Content elements (see section 3.7). See
                     the payment scheme supplement for the definition
                     of its content.

                     Note that:
                      o the values of the Name attribute of each
                        packaged content element are defined by the
                        Payment Protocol Supplement
                      o the value of each Name must be unique within a
                        Payment where a Payment is defined as all
                        Payment Scheme or Payment Receipt Components
                        with the same value of the PaymentRef attribute

7.11 Payment Receipt Component

  A Payment Receipt is a record of a payment which demonstrates how
  much money has been paid or received. It is distinct from a purchase
  receipt in that it contains no record of what was being purchased.

  Typically the content of a Payment Receipt Component will contain
  data which describes:

  o  the amount paid and its currency

  o  the date and time of the payment

  o  internal reference numbers which identify the payment to the
     payment system

  o  potentially digital signatures generated by the payment method
     which can be used to prove after the event that the payment
     occurred.

  If the Payment Method being used provides the facility then the
  Payment Receipt Component should contain payment protocol messages,
  or references to messages, which prove the payment occurred.

  The precise definition of the content is Payment Method dependent.
  Refer to the supplement for the payment method being used to
  determine the rules that apply.

  Information contained in the Payment Receipt Component should be
  displayed or otherwise made available to the Consumer.





Burdett                      Informational                    [Page 126]

RFC 2801                       IOTP/1.0                       April 2000


  Note: If the Payment Receipt Component contains Payment Protocol
  Messages, then the Messages will need to be processed by Payment
  Method software to convert it into a format which can be understood
  by the Consumer

   The definition of a Payment Receipt Component is as follows.

  <!ELEMENT PayReceipt (PackagedContent*) >
  <!ATTLIST PayReceipt
   ID                 ID      #REQUIRED
   PaymentRef         NMTOKEN #REQUIRED
   PayReceiptNameRefs NMTOKENS #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                  An identifier which uniquely identifies the
                      Payment Receipt Component within the IOTP
                      Transaction.

  PaymentRef          Contains an Element Reference (see section 3.5)
                      to the Payment Component (see section 7.9) to
                      which this payment receipt applies

  PayReceiptNameRefs  Optionally contains a list of the values of the
                      Name attributes of Packaged Content elements that
                      together make up the receipt. The Packaged
                      Content elements are contained either within:
                       o Payment Scheme Data components exchanged
                         between the Payment Handler and the Consumer
                         roles during the Payment, and/or
                       o the Payment Receipt component itself.
                      Note that:
                       o each payment scheme defines in its supplement
                         the Names of the Packaged Content elements
                         that must be listed in this attribute (if
                         any).
                       o if a Payment Scheme Component contains
                         Packaged Content elements with a name that
                         matches a name within PayReceiptNameRefs, then
                         those Payment Scheme Components must be
                         referenced by Digests in the Payment Response
                         signature component (if such a signature is
                         being used)

                      The client software should save all the
                      components referenced so that the payment receipt
                      can be reconstructed when required.



Burdett                      Informational                    [Page 127]

RFC 2801                       IOTP/1.0                       April 2000


  ContentSoftwareId   See section 14. Glossary.

  Content:

  PackagedContent    Optionally contains payment scheme payment receipt
                     information as Packaged Content elements (see
                     section 3.7). See the payment scheme supplement
                     for the definition of its content.

                     Note that:
                      o the values of the Name attribute of each
                        packaged content element are defined by the
                        Payment Protocol Supplement
                      o the value of each Name must be unique within a
                        Payment where a Payment is defined as all
                        Payment Scheme or Payment Receipt Components,
                        with the same value of the PaymentRef attribute

  Note that either the PayReceiptNameRefs attribute, the
  PackagedContent element, or both must be present.

7.12 Payment Note Component

  The Payment Note Component contains additional, non payment related,
  information which the Payment Handler wants to provide to the
  Consumer.  For example, if a withdrawal or deposit were being made
  then it could contain information on the remaining balance on the
  account after the transfer was complete. The information should
  duplicate information contained within the Payment Receipt Component.

  Information contained in the Payment Note Component should be
  displayed or otherwise made available to the Consumer. For
  interoperability, the Payment Note Component should support, as a
  minimum, the content types of "Plain Text", HTML and XML. Its
  definition is as follows.

  <!ELEMENT PaymentNote (PackagedContent+) >
  <!ATTLIST PaymentNote
    ID                ID      #REQUIRED
    ContentSoftwareId CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Payment Receipt Component within the IOTP
                     Transaction.

  ContentSoftwareId  See section 14. Glossary.



Burdett                      Informational                    [Page 128]

RFC 2801                       IOTP/1.0                       April 2000


  Content:

  PackagedContent    Contains additional, non payment related,
                     information which the Payment Handler wants to
                     provide to the Consumer as one or more Packaged
                     Content elements (see section 3.7).

7.13 Delivery Component

  The Delivery Element contains information required to deliver goods
  or services. Its definition is as follows.

  <!ELEMENT Delivery (DeliveryData?, PackagedContent*) >
  <!ATTLIST Delivery
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   DelivExch          (True | False) #REQUIRED
   DelivAndPayResp    (True | False) #REQUIRED
   ActionOrgRef       NMTOKEN #IMPLIED >

  Attributes:

  ID                  An identifier which uniquely identifies the
                      Delivery Component within the IOTP Transaction.

  xml:lang            Defines the language used by attributes or child
                      elements within this component, unless overridden
                      by an xml:lang attribute on a child element. See
                      section 3.8 Identifying Languages.

  DelivExch           Indicates if this IOTP Transaction includes the
                      messages associated with a Delivery Exchange.
                      Valid values are:
                       o True indicates it does include a Delivery
                         Exchange
                       o False indicates it does not include a
                         Delivery Exchange

                      If set to true then a DeliveryData element must
                      be present. If set to false it may be absent.

  DelivAndPayResp     Indicates if the Delivery Response Block (see
                      section 8.11) and the Payment Response Block (see
                      section 8.9 ) are combined into one IOTP Message.
                      Valid values are:
                       o True indicates both blocks will be in the
                         same IOTP Message, and




Burdett                      Informational                    [Page 129]

RFC 2801                       IOTP/1.0                       April 2000


                       o False indicates each block will be in a
                         different IOTP Message

                      DelivAndPayResp should not be true if DelivExch
                      is False.

                      In practice combining the Delivery Response Block
                      and Payment Response Block is only likely to be
                      practical if the Merchant, the Payment Handler
                      and the Delivery Handler are the same
                      Organisation since:
                       o the Payment Handler must have access to Order
                         Component information so that they know what
                         to deliver, and
                       o the Payment Handler must be able to carry out
                         the delivery

  ActionOrgRef        An Element Reference to the Organisation
                      Component of the Delivery Handler for this
                      delivery.

  Content:

  DeliveryData       Contains details about how the delivery will be
                     carried out. See 7.13.1 Delivery Data Element
                     below.

  PackagedContent    Contains "user" data defined for the Merchant
                     which is required by the Delivery Handler as one
                     or more Packaged Content Elements see section 3.7.

7.13.1 Delivery Data Element

  The DeliveryData element contains information about where and how
  goods are to be delivered. Its definition is as follows.

  <!ELEMENT DeliveryData (PackagedContent*) >
  <!ATTLIST DeliveryData
   xml:lang           NMTOKEN #IMPLIED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   DelivMethod        NMTOKEN #REQUIRED
   DelivToRef         NMTOKEN #REQUIRED
   DelivReqNetLocn    CDATA   #REQUIRED
   SecDelivReqNetLocn CDATA   #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >





Burdett                      Informational                    [Page 130]

RFC 2801                       IOTP/1.0                       April 2000


  Attributes:

  xml:lang            Defines the language used by attributes within
                      this component. See section 3.8 Identifying
                      Languages.

  OkFrom              The date and time in [UTC] format after which the
                      Delivery Handler may accept for processing a
                      Delivery Request Block (see section 8.10).

  OkTo                The date and time in [UTC] format before which
                      the Delivery Handler may accept for processing a
                      Delivery Request Block.

  DelivMethod         Indicates the method by which goods or services
                      may be delivered. Valid values are:
                       o Post the goods will be delivered by post or
                         courier
                       o Web the goods will be delivered
                         electronically in the Delivery Note Component
                       o Email the goods will be delivered
                         electronically by e-mail

                      Values of DelivMethod are managed under the
                      procedure described in section 12 IANA
                      Considerations which allows user defined codes to
                      be defined.

  DelivToRef          The Element Reference (see section 3.4) of an
                      Organisation Component within the IOTP
                      Transaction which has a role of DelivTo. The
                      information in this block is used to determine
                      where delivery is to be made. It must be
                      compatible with DelivMethod. Specifically if the
                      DelivMethod is:
                       o Post, then the there must be a Postal Address
                         Element containing sufficient information for
                         a postal delivery,
                       o Web, then there are no specific requirements.
                         The information will be sent in a web page
                         back to the Consumer
                       o Email, then there must be Contact Information
                         Element with a valid e-mail address

  DelivReqNetLocn     This contains the Net Location to which an
                      unsecured Delivery Request Block (see section
                      8.10) which contains the Delivery Component
                      should be sent.



Burdett                      Informational                    [Page 131]

RFC 2801                       IOTP/1.0                       April 2000


                      The content of this attribute is dependent on the
                      Transport Mechanism and must conform to
                      [RFC1738].

  SecDelivReqNetLocn  This contains the Net Location to which a secured
                      Delivery Request Block (see section 8.10) which
                      contains the Delivery Component should be sent.

                      A secured delivery request involves the use of a
                      secure channel such as [SSL/TLS] in order to
                      communicate with the Payment Handler.

                      The content of this attribute is dependent on the
                      Transport Mechanism must conform to [RFC1738].

                      See also Section 3.9 Secure and Insecure Net
                      Locations.

  ContentSoftwareId   See section 14. Glossary.

  Content:

  PackagedContent    Additional information about the delivery as one
                     or more Packaged Content elements (see section
                     3.7) provided to the Delivery Handler by the
                     merchant.

7.14 Consumer Delivery Data Component

  A Consumer Delivery Data Component is used by a Consumer to specify
  an identifier that can be used by the Consumer to identify the
  Delivery.

  Its definition is as follows:

  <!ELEMENT ConsumerDeliveryData EMPTY >
  <!ATTLIST ConsumerDeliveryData
   ID                 ID      #REQUIRED
   ConsumerDeliveryId CDATA   #REQUIRED>

  Attributes:

  ID                  An identifier which uniquely identifies the
                      Consumer Delivery Data Component within the IOTP
                      Transaction.






Burdett                      Informational                    [Page 132]

RFC 2801                       IOTP/1.0                       April 2000


  ConsumerDeliveryId  An identifier specified by the Consumer which, if
                      returned by the Delivery Handler will enable the
                      Consumer to identify which Delivery is being
                      referred to.

7.15 Delivery Note Component

  A Delivery Note contains delivery instructions about the delivery of
  goods or services or potentially the actual Delivery Information
  itself.  It is information which the person or Organisation receiving
  the Delivery Note can use when delivery occurs.

  For interoperability, the Delivery Note Component Packaged Content
  should support both Plain Text, HTML and XML.

  It's definition is as follows.

  <!ELEMENT DeliveryNote (PackagedContent+) >
  <!ATTLIST DeliveryNote
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   DelivHandlerDelivId CDATA  #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >

  Attributes:

  ID                   An identifier which uniquely identifies the
                       Delivery Note Component within the IOTP
                       Transaction.

  xml:lang             Defines the language used by attributes or child
                       elements within this component, unless
                       overridden by an xml:lang attribute on a child
                       element. See section 3.8 Identifying Languages.

  DelivHandlerDelivId  An optional identifier specified by the Delivery
                       Handler which, if returned by the Consumer in
                       another Delivery Component, or by other means,
                       will enable the Delivery Handler to identify
                       which Delivery is being referred to. It is
                       required on every Delivery Component apart from
                       the one contained in a Delivery Request Block.

                       An example use of this attribute is to contain a
                       delivery tracking number.

  ContentSoftwareId    See section 14. Glossary.




Burdett                      Informational                    [Page 133]

RFC 2801                       IOTP/1.0                       April 2000


  Content:

  PackagedContent    Contains actual delivery note information as one
                     or more Packaged Content elements (see section
                     3.7).

  Note: If the content of the Delivery Message is a Mime message then
  the Delivery Note may trigger an application which causes the actual
  delivery to occur.

7.16 Status Component

  A Status Component contains status information about the business
  success or failure (see section 4.2) of a process.

  Its definition is as follows.

  <!ELEMENT Status EMPTY >
  <!ATTLIST Status
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   StatusType         NMTOKEN #REQUIRED
   ElRef              NMTOKEN #IMPLIED
   ProcessState (NotYetStarted | InProgress |
       CompletedOk | Failed | ProcessError) #REQUIRED
   CompletionCode     NMTOKEN #IMPLIED
   ProcessReference   CDATA   #IMPLIED
   StatusDesc         CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the Status
                     Component within the IOTP Transaction.

  xml:lang           Defines the language used by attributes within
                     this component. See section 3.8 Identifying
                     Languages.

  StatusType         Indicates the type of Document Exchange which the
                     Status is reporting on. It may be set to either
                     Offer, Payment, Delivery, Authentication or
                     Undefined.

                     Undefined means that the type of document exchange
                     could not be identified. This is caused by an
                     error in the initial input message of the
                     exchange.




Burdett                      Informational                    [Page 134]

RFC 2801                       IOTP/1.0                       April 2000


                     Values of StatusType are managed under the
                     procedure described in section 12 IANA
                     Considerations which also allows user defined
                     values of StatusType to be defined.

  ElRef              If the StatusType is not set to Undefined then
                     ElRef contains an Element Reference (see section
                     3.5) to the Component for which the Status is
                     being described. It must refer to either:
                      o an Order Component (see section 7.5), if the
                        StatusType is Offer,
                      o a Payment Component (see section 7.9), if the
                        StatusType is Payment, or
                      o a Delivery Component (see section 7.13), if
                        the StatusType is Delivery
                      o an Authentication Request Component (see
                        section 7.2) if the StatusType is
                        Authentication.

  ProcessState       Contains a State Code which indicates the current
                     state of the process being carried out. Valid
                     values for ProcessState are:
                      o NotYetStarted. A Request Block has been
                        received but the process has not yet started
                      o InProgress. Processing of the Request Block
                        has started but it is not yet complete
                      o CompletedOk. The processing of the Request
                        Block has completed successfully without any
                        errors
                      o Failed. The processing of the Request Block
                        has failed because of a Business Error (see
                        section 4.2)
                      o ProcessError. This value is only used when the
                        Status Component is being used in connection
                        with an Inquiry Request Trading Block (see
                        section 8.12). It indicates there was a
                        Technical Error (see section 4.1) in the
                        Request Block which is being processed or some
                        internal processing error.

                     Note that this code reports on the processing of a
                     Request Block. Further, asynchronous processing
                     may occur after the Response Block associated with
                     the Process has been sent.







Burdett                      Informational                    [Page 135]

RFC 2801                       IOTP/1.0                       April 2000


  CompletionCode     Indicates how the process completed. Valid values
                     for the CompletionCode are given below together
                     with the conditions when it must be present and
                     indications on when recovery from failures are
                     possible.

                     A CompletionCode is a maximum of 14 characters
                     long.

  ProcessReference   This optional attribute holds a reference for the
                     process whose status is being reported. It may
                     hold the following values:
                      o when StatusType is set to Offer, it should
                        contain the OrderIdentifier from the Order
                        Component
                      o when StatusType is set to Payment, it should
                        contain the PaymentHandlerPayId from the
                        Payment Scheme Data Component
                      o when StatusType is set to Delivery, it should
                        contain the DelivHandlerDelivId from the
                        Delivery Note Component
                      o when StatusType is set to Authentication, it
                        should contain the AuthenticationId from the
                        Authentication Request Component

                     This attribute should be absent in the Inquiry
                     Request message when the Consumer has not been
                     given such a reference number by the IOTP Service
                     Provider.

                     This attribute can be used inside an Inquiry
                     Response Block (see section 8.13) to give the
                     reference number for a transaction which has
                     previously been unavailable.

                     For example, the package tracking number might not
                     be assigned at the time a delivery response was
                     received. However, if the Consumer issues a
                     Baseline Transaction Status Inquiry later, the
                     Delivery Handler can put the package tracking
                     number into this attribute in the Inquiry Response
                     message and send it back to the Consumer.

  StatusDesc         An optional textual description of the current
                     status of the process in the language identified
                     by xml:lang.





Burdett                      Informational                    [Page 136]

RFC 2801                       IOTP/1.0                       April 2000


7.16.1 Offer Completion Codes

  The Completion Code is only required if the ProcessState attribute is
  set to Failed. The following table contains the valid values for the
  CompletionCode that may be used and indicates whether or not recovery
  might be possible. It is recommended that the StatusDesc attribute is
  used to provide further explanation where appropriate.

      Value                            Description

  AuthError        Authentication Error. The check of the
                   Authentication Response which was carried out has
                   failed.

                   Recovery may be possible by the Consumer re-
                   submitting a new Authentication Response Block with
                   corrected information.

  ConsCancelled    Consumer Cancelled. The Consumer decides to cancel
                   the transaction for some reason. This code is only
                   valid in a Status Component contained in a Cancel
                   Block or an Inquiry Response Block.

                   No recovery possible.

  MerchCancelled   Offer Cancelled. The Merchant declines to generate
                   an offer for some reason and cancels the
                   transaction. This code is only valid in a Status
                   Component contained in a Cancel Block or an Inquiry
                   Response Block.

                   No recovery possible.

  Unspecified      Unspecified error. There is some unknown problem or
                   error which does not fall into one of the other
                   CompletionCodes.

                   No recovery possible.

  TimedOutRcvr     Recoverable Time Out. Messages were resent but no
                   response received. The document exchange has
                   therefore "Timed Out". This code is only valid on a
                   Transaction Inquiry.

                   Recovery is possible if the last message from the
                   other Trading Role is received again.





Burdett                      Informational                    [Page 137]

RFC 2801                       IOTP/1.0                       April 2000


  TimedOutNoRcvr   Non Recoverable Time Out. Messages were resent but
                   no response received. The document exchange has
                   therefore "Timed Out". This code is only valid on a
                   Transaction Inquiry.

                   No recovery possible.

7.16.2 Payment Completion Codes

  The CompletionCode is only required if the ProcessState attribute is
  set to Failed. The following table contains the valid values for the
  CompletionCode that may be used and indicates where recovery may be
  possible. It is recommended that the StatusDesc attribute is used by
  individual payment schemes to provide further explanation where
  appropriate.

        Value                           Description

  BrandNotSupp       Brand not supported. The payment brand is not
                     supported by the Payment Handler.

                     See below for recovery options.

  CurrNotSupp        Currency not supported. The currency in which the
                     payment is to be made is not supported by either
                     the Payment Instrument or the Payment Handler.

                     If the payment is Brand Independent, then the
                     Consumer may recover by selecting a different
                     currency, if available, or a different brand. Note
                     that this may involve a different Payment Handler.

  ConsCancelled      Consumer Cancelled. The Consumer decides to cancel
                     the payment for some reason. This code is only
                     valid in a Status Component contained in a Cancel
                     Block or an Inquiry Response Block.

                     Recovery is not possible.

  PaymtCancelled     Payment Cancelled. The Payment Handler declines to
                     complete the payment for some reason and cancels
                     the transaction. This code is only valid in a
                     Status Component contained in a Cancel Block or an
                     Inquiry Response Block.

                     See below for recovery options.





Burdett                      Informational                    [Page 138]

RFC 2801                       IOTP/1.0                       April 2000


  AuthError          Authentication Error. The Payment Scheme specific
                     authentication check which was carried out has
                     failed.

                     Recovery may be possible. See the payment scheme
                     supplement to determine what is allowed.

  InsuffFunds        Insufficient funds. There are insufficient funds
                     available for the payment to be made.

                     See below for recovery options.

  InstBrandInvalid   Payment Instrument not valid for Brand. A Payment
                     Instrument is being used which does not correspond
                     with the Brand selected. For example a Visa credit
                     card is being used when MasterCard was selected as
                     the Brand.

                     See below for recovery options.

  InstNotValid       Payment instrument not valid for trade. The
                     Payment Instrument cannot be used for the proposed
                     type of trade, for some reason.

                     See below for recovery options.

  BadInstrument      Bad instrument. There is a problem with the
                     Payment Instrument being used which means that it
                     is unable to be used for the payment.

                     See below for recovery options.

  Unspecified        Unspecified error. There is some unknown problem
                     or error which does not fall into one of the other
                     CompletionCodes. The StatusDesc attribute should
                     provide the explanation of the cause.

                     See below for recovery options.

  TimedOutRcvr       Recoverable Time Out. Messages were resent but no
                     response received. The document exchange has
                     therefore "Timed Out". This code is only valid on
                     a Transaction Inquiry.

                     Recovery is possible if the last message from the
                     other Trading Role is received again.





Burdett                      Informational                    [Page 139]

RFC 2801                       IOTP/1.0                       April 2000


  TimedOutNoRcvr     Non Recoverable Time Out. Messages were resent but
                     no response received. The document exchange has
                     therefore "Timed Out". This code is only valid on
                     a Transaction Inquiry.

                     No recovery possible.

  If the Payment is Brand Independent, then recovery may be possible
  for some values of the Completion Code, by the Consumer selecting
  either a different payment brand or a different payment instrument
  for the same brand. Note that this might involve a different Payment
  Handler. The codes to which this applies are: BrandNotSupp,
  PaymtCancelled, InsuffFunds, InstBrandInvalid, InstNotValid,
  BadInstrument and Unspecified.

  Recovery from Payments associated with Brand Dependent purchases is
  only possible, if the Brand Selection component sent by the Merchant
  to the Consumer does not change. In practice this means that the same
  Brand, Protocol Amount and PayProtocol elements must be used. All
  that can change is the Payment Instrument. Any other change will
  invalidate the Merchant's Offer as a changed selection will
  invalidate the Offer Response.

7.16.3 Delivery Completion Codes

  The following table contains the valid values for the CompletionCode
  attribute for a Delivery. It is recommended that the StatusDesc
  attribute is used to provide further explanation where appropriate.

       Value                           Description

  BackOrdered     Back Ordered. The goods to be delivered are on order
                  but they have not yet been received. Shipping will be
                  arranged when they are received. This is only valid
                  if ProcessState is CompletedOk.

                  Recovery is not possible.

  PermNotAvail    Permanently Not Available. The goods are permanently
                  unavailable and cannot be re-ordered. This is only
                  valid if ProcessState is Failed.

                  Recovery is not possible.

  TempNotAvail    Temporarily Not Available. The goods are temporarily
                  unavailable and may become available if they can be
                  ordered. This is only valid if ProcessState is
                  CompletedOk.



Burdett                      Informational                    [Page 140]

RFC 2801                       IOTP/1.0                       April 2000


                  Recovery is not possible.

  ShipPending     Shipping Pending. The goods are available and are
                  scheduled for shipping but they have not yet been
                  shipped. This is only valid if ProcessState is
                  CompletedOk.

                  Recovery is not possible.

  Shipped         Goods Shipped. The goods have been shipped.
                  Confirmation of delivery is awaited. This is only
                  valid if ProcessState is CompletedOk.

                  Recovery is not possible.

  ShippedNoConf   Shipped - No Delivery Confirmation. The goods have
                  been shipped but it is not possible to confirm
                  delivery of the goods. This is only valid if
                  ProcessState is CompletedOk.

                  Recovery is not possible.

  ConsCancelled   Consumer Cancelled. The Consumer decides to cancel
                  the delivery for some reason. This code is only valid
                  in a Status Component contained in a Cancel Block or
                  an Inquiry Response Block.

                  Recovery is not possible.

  DelivCancelled  Delivery Cancelled. The Delivery Handler declines to
                  complete the Delivery for some reason and cancels the
                  transaction. This code is only valid in a Status
                  Component contained in a Cancel Block or an Inquiry
                  Response Block.

                  Recovery is not possible.

  Confirmed       Confirmed. All goods have been delivered and
                  confirmation of their delivery has been received.
                  This is only valid if ProcessState is CompletedOk.

                  Recovery is not possible.

  Unspecified     Unspecified error. There is some unknown problem or
                  error which does not fall into one of the other
                  CompletionCodes. The StatusDesc attribute should
                  provide the explanation of the cause.




Burdett                      Informational                    [Page 141]

RFC 2801                       IOTP/1.0                       April 2000


                  Recovery is not possible.

  TimedOutRcvr    Recoverable Time Out. Messages were resent but no
                  response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.

                  Recovery is possible if the last message from the
                  other Trading Role is received again.

  TimedOutNoRcvr  Non Recoverable Time Out. Messages were resent but no
                  response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.

                  No recovery possible.

  Note: Recovery from failed, or partially completed deliveries is not
  possible. The Consumer should use the Transaction Status Inquiry
  Transaction (see section 9.2.1) to determine up-to- date information
  on the current state.

7.16.4 Authentication Completion Codes

  The Completion Code is only required if the ProcessState attribute is
  set to Failed. The following table contains the valid values for the
  CompletionCode that may be used. It is recommended that the
  StatusDesc attribute is used to provide further explanation where
  appropriate.

       Value                           Description

  AutEeCancel     Authenticatee Cancel. The Organisation being
                  authenticated declines to be authenticated for some
                  reason. This could be, for example because the
                  signature on an Authentication Request was invalid or
                  the Authenticator was not known or acceptable to the
                  Authenticatee.

                  Recovery is not possible.

  AutOrCancel     Authenticator Cancel. The Organisation requesting
                  authentication declines to validate the
                  Authentication Response received for some reason and
                  cancels the transaction.

                  Recovery is not possible.




Burdett                      Informational                    [Page 142]

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  NoAuthReq       Authentication Request Not Available. The
                  Authenticatee does not have the data that must be
                  provided so that they may be successfully
                  authenticated. For example a password may have been
                  forgotten, the Authenticatee has not yet become a
                  member, or a smart card token is not present.

                  Recovery is not possible

  AuthFailed      Authentication Failed. The Authenticator checked the
                  Authentication Response but the authentication failed
                  for some reason. For example a password may have been
                  incorrect.

                  Recovery may be possible by the Authenticatee re-
                  sending a revised Authentication Response with
                  corrected data.

  TradRolesIncon  Trading Roles Inconsistent. The Trading Roles
                  contained within the TradingRoleList attribute of the
                  Trading Role Information Request Component (see
                  section 7.4) are inconsistent with the Trading Role
                  which the Authenticatee is taking in the IOTP
                  Transaction or is able to take. Examples of
                  inconsistencies include:
                   o asking a PaymentHandler for DeliveryHandler
                    information
                   o asking a Consumer for Merchant information

                  Recovery may be possible by the Authenticator re-
                  sending a revised Authentication Request Block with
                  corrected information.

  Unspecified     Unspecified error. There is some unknown problem or
                  error which does not fall into one of the other
                  CompletionCodes.

                  Recovery is not possible.

  TimedOutRcvr    Recoverable Time Out. Messages were resent but no
                  response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.

                  Recovery is possible if the last message from the
                  other Trading Role is received again.





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  TimedOutNoRcvr  Non Recoverable Time Out. Messages were resent but no
                  response received. The document exchange has
                  therefore "Timed Out". This code is only valid on a
                  Transaction Inquiry.

                  No recovery possible.

7.16.5 Undefined Completion Codes

  The Completion Code is only required if the ProcessState attribute is
  set to Failed. The following table contains the valid values for the
  CompletionCode that may be used. It is recommended that the
  StatusDesc attribute is used to provide further explanation where
  appropriate.

       Value                           Description

  InMsgHardError  Input Message Hard Error. The type of Request Block
                  could not be identified or was inconsistent.
                  Therefore no single Document Exchange could be
                  identified. This will cause a Hard Error in the
                  transaction

7.16.6 Transaction Inquiry Completion Codes

  The Completion Code is only required if the ProcessState attribute is
  set to Failed. The following table contains the valid values for the
  CompletionCode that may be used. It is recommended that the
  StatusDesc attribute is used to provide further explanation where
  appropriate.

       Value                           Description

  UnAuthReq       Unauthorised Request. The recipient of the
                  Transaction Status Request declines to respond to the
                  request.

7.17 Trading Role Data Component

  The Trading Role Data Component contains opaque data which needs to
  be communicated between the Trading Roles involved in an IOTP
  Transaction.

  Trading Role Components identify:

  o the Organisation that generated the component, and

  o the Organisation that is to receive it.



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  They are first generated and included in a "Response" Block, and then
  copied to the appropriate "Request" Block. For example a Payment
  Handler might need to inform a Delivery Handler that a credit card
  payment had been authorised but not captured. There may also be other
  information that the Payment Handler has generated where the format
  is privately agreed with the Delivery Handler which needs to be
  communicated. In another example a Merchant might need to provide a
  Payment Handler with some specific information about a Consumer so
  that consumer can acquire double loyalty points with the payment.

  Its definition is as follows.

  <!ELEMENT TradingRoleData (PackagedContent+) >
  <!ATTLIST TradingRoleData
    ID                ID      #REQUIRED
    OriginatorElRef   NMTOKEN #REQUIRED
    DestinationElRefs NMTOKENS #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Trading Role Data Component within the IOTP
                     Transaction.

  OrginatorElRef     Contains an element reference to the Organisation
                     Component of the Organisation that created the
                     Trading Role Data Component and included it in a
                     "Response" Block (e.g., an Offer Response or a
                     Payment Response Block).

  DestinationElRefs  Contains element references to the Organisation
                     Components of the Organisations that are to
                     receive the Trading Role Data Component in a
                     "Request" Block (e.g., either a Payment Request or
                     a Delivery Request Block).

  Content:

  PackagedContent    This contains the data which is to be sent between
                     the various Trading Roles as one or more
                     PackagedContent elements see section 3.7.

7.17.1 Who Receives a Trading Role Data Component

  The rules for deciding what to do with Trading Role Data Components
  are described below.





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  o  whenever a Trading Role Data Component is received in a "Response"
     block identify the Organisation Components of the Organisations
     that are to receive it as identified by the DestinationElRefs
     attribute.

  o  whenever a "Request" Block is being sent, check to see if it is
     being sent to one of the Organisations identified by the
     DestinationElRefs attribute. If it is then include in the
     "Request" block:

     -  the Trading Role Data Component as well as,

     -  the Organisation Component of the Organisation identified by
        the OriginatorElRef attribute (if not already present)

7.18 Inquiry Type Component

  The Inquiry Type Component contains the information which indicates
  the type of process that is being inquired upon. Its definition is as
  follows.

  <!ELEMENT InquiryType EMPTY >
  <!ATTLIST InquiryType
   ID                 ID      #REQUIRED
   Type               NMTOKEN #REQUIRED
   ElRef              NMTOKEN #IMPLIED
   ProcessReference   CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Inquiry Type Component within the IOTP
                     Transaction.

  Type               Contains the type of inquiry. Valid values for
                     Type are:
                      o Offer. The inquiry is about the status of an
                        offer and is addressed to the Merchant.
                      o Payment. The inquiry is about the status of a
                        payment and is addressed to the Payment
                        Handler.
                      o Delivery. The inquiry is about the status of a
                        delivery and addressed to the Delivery Handler.

  ElRef              Contains an Element Reference (see section 3.5) to
                     the component to which this Inquiry Type Component
                     applies. That is,
                      o TPO Block when Type is Offer



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                      o Payment Component when Type is Payment
                      o Delivery Component when Type is Delivery

  ProcessReference   Optionally contains a reference to the process
                     being inquired upon. It should be set if the
                     information is available. For the definition of
                     the values it may contain, see the
                     ProcessReference attribute of the Status Component
                     (see section 7.16).

7.19 Signature Component

  Note: Definitions of the XML structures for signatures and
  certificates are described in the document titled "Digital Signatures
  for the Internet Open Trading Protocol" by Kent Davidson and Yoshiaki
  Kawatsura published at the same time as this document - see
  [IOTPDSIG].

  In the future it is anticipated that future versions of IOTP will
  adopt a whatever method for digitally signing XML becomes the
  standard.

  Each Signature Component digitally signs one or more Blocks or
  Components including other Signature Components.

  The Signature Component:

  o  contains digests of one or more Blocks or Components in one or
     more IOTP Messages within the same IOTP Transaction and places the
     result in a Digest Element

  o  concatenates these Digest elements with other information on the
     type of signature, the originator and potential recipients of the
     signature and details of the signature algorithms being used and
     places them in a Manifest element, and

  o  signs the Manifest element using the optional certificate
     identified in the Certificate element within the Signature Block
     placing the result in a Value element within a Signature Component

  Note that there may be multiple Value elements that contain
  signatures of a Manifest Element.

  A Signature Component can be one of four types either:

  o an Offer Response Signature,

  o a Payment Response Signature,



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  o a Delivery Response Signature, or

  o an Authentication Response Signature.

  For a general explanation of signatures see section 6 Digital
  Signatures.

7.19.1 IOTP usage of signature elements and attributes

  Definitions of the elements and attributes are contained in
  [IOTPDSIG].  The following contains additional information that
  describes how these elements and attributes are used by IOTP.

  SIGNATURE ELEMENT

  The ID attribute is mandatory.

  MANIFEST ELEMENT

  The optional LocatorHrefBase attribute contains text which should be
  concatenated before the text contained in the LocatorHREF attribute
  of all Digest elements within the Manifest.

  Its purpose is to reduce the size of LocatorHREF attribute values
  since the first part of the LocatorHREF attributes in the same
  signature are likely to be the same.

  Typically, within IOTP, it will contain all the characters in a
  LocatorHref attribute up to the sharp ("#") character (see
  immediately below).

  ALGORITHM AND PARAMETER ELEMENTS

  The algorithm element identifies the algorithms used in generating
  the signature. The type of the algorithm is defined by the value of
  the Type attribute which indicates if it is to be used as a Digest
  algorithm, a Signature algorithm or a Key Agreement algorithm.

  The following Digest algorithms must be implemented:

  o  a [DOM-HASH] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:ibm:dom-hash"

  o  a [SHA1] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:fips:sha1", and

  o  a [MD5] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:rsa:md5"



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  o  The following Signature algorithms must be implemented:

  o  a [DSA] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:us.gov:dsa"

  o  a [HMAC] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:ibm:hmac"

  It is recommended that the following Signature algorithm is also
  implemented:

  o  a [RSA] algorithm. This is identified by setting the Name
     attribute of the Algorithm element to "urn:rsa:rsa"

  In addition other payment scheme specific algorithms may be used. In
  this case the value of the name attribute to use is specified in the
  payment scheme supplement for that algorithm.

  One algorithm may make use of other algorithms by use of the
  Parameter element, for example:

  <Algorithm ID=A1 type="digest" name="urn:ibm:dom-hash">
    <Parameter type='AlgorithmRef'>A2</Parameter>
  </Algorithm>
  <Algorithm ID=A2 type="digest" name="urn:fips:sha1">
  </Algorithm>
  <Algorithm ID=A3 type="signature" name="urn:ibm:hmac">
      <Parameter type='AlgorithmRef'>A1</Parameter>
  </Algorithm>

  DIGEST ELEMENT

  The LocatorHREF attribute identifies the IOTP element which is being
  digitally signed. Specifically it consists of:

  o  the value of the IotpTransId attribute of the Transaction ID
     Component, followed by:

  o  a sharp character, i.e. "#", followed by

  o  an Element Reference (see section 3.5) to the element within the
     IOTP Transaction which is the subject of the digest.

  Before analysing the structure of the LocatorHREF attribute, it must
  be concatenated with the value of the LocatorHrefBase attribute of
  the Manifest element (see immediately above).





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  ATTRIBUTE ELEMENT

  There must be one and only one Attribute Element that contains a Type
  attribute with a value of IOTP Signature Type and with content set to
  either: OfferResponse, PaymentResponse, DeliveryResponse,

  AuthenticationRequest, AuthenticationResponse, PingRequest or
  PingResponse; depending on the type of the signature.

  Values of the content of the Attribute element are controlled under
  the procedures defined in section 12 IANA Considerations which also
  allows user defined values to be defined.

  The Critical attribute must be set to true.

  ORIGINATORINFO ELEMENT

  The OriginatorRef attribute of the OriginatorInfo element must always
  be present and contain an Element Reference (see section 3.5) to the
  Organisation Component of the Organisation that generated the
  Signature Component.

  RECIPIENTINFO ELEMENT

  The RecipientRefs attribute contains a list of Element References
  (see section 3.5), that point to the Organisations that might need to
  validate the signature. For details see below.

7.19.2 Offer Response Signature Component

  The Manifest Element of a signature which has a type of OfferResponse
  should contain Digest elements for the following Components:

  o  the Transaction Id Component (see section 3.3.1) of the IOTP
     message that contains the Offer Response Signature

  o  the Transaction Reference Block (see section 3.3) of the IOTP
     Message that contains the Offer Response Signature

  o  from the TPO Block:

     -  the Protocol Options Component

     -  each of the Organisation Components

     -  each of the Brand List Components





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  o  optionally, all the Brand Selection Components if they were sent
     to the Merchant in a TPO Selection Block

  o  from the Offer Response Block:

     - the Order Component

     - each of the Payment Components

     - the Delivery Component

     - each of the Authentication Request Components

     - any Trading Role Data Components

  The Offer Response Signature should also contain Digest elements for
  the components that describe each of the Organisations that may or
  will need to verify the signature. This involves:

  o  if the Merchant has received a TPO Selection Block containing
     Brand Selection Components, then generate a Digest element for the
     Payment Handler identified by the Brand Selection Component and
     the Delivery Handler identified by the Delivery Component. See
     section 6.3.1 Check Request Block sent Correct Organisation for a
     description of how this can be done.

  o  if the Merchant is not expecting to receive a TPO Selection Block
     then generate a Digest element for the Delivery Handler and all
     the Payment Handlers that are involved.

7.19.3 Payment Receipt Signature Component

  The Manifest Element of the Payment Receipt Signature Component
  should contain Digest Elements for the following Components:

  o  the Transaction Id Component (see section 3.3.1) of the IOTP
     message that contains the Payment Receipt Signature

  o  the Transaction Reference Block (see section 3.3) of the IOTP
     Message that contains the Payment Receipt Signature

  o  the Offer Response Signature Component

  o  the Payment Receipt Component

  o  the Payment Note Component

  o  the Status Component



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  o  the Brand Selection Component.

  o  any Trading Role Data Components

7.19.4 Delivery Response Signature Component

  The Manifest Element of the Delivery Response Signature Component
  should contain Digest Elements for the following Components:

  o  the Transaction Id Component (see section 3.3.1) of the IOTP
     message that contains the Delivery  Response Signature

  o  the Transaction Reference Block (see section 3.3) of the IOTP
     Message that contains the Delivery Response Signature

  o  the Consumer Delivery Data component contained in the preceding
     Delivery Request (if any)

  o  the Signature Components contained in the preceding Delivery
     Request (if any)

  o  the Status Component

  o  the Delivery Note Component

7.19.5 Authentication Request Signature Component

  The Manifest Element of the Authentication Request Signature
  Component should contain Digest Elements for the following
  Components:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the TPO Block :

     -  the Protocol Options Component

     -  the Organisation Component

  o  the following components of the Authentication Request Block:

     -  the Authentication Request Component(s) (if present)




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     -  the Trading Role Information Request Component (if present)

7.19.6 Authentication Response Signature Component

  The Manifest Element of the Authentication Response Signature
  Component should contain Digest Elements for the following
  Components:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the Authentication Request Block:

     -  the Authentication Request Component that was used in the
        Authentication (if present)

     -  the Trading Role Information Request Component (if present)

  o  the Organisation Components contained in the Authentication
     Response Block

7.19.7 Inquiry Request Signature Component

  If the Inquiry Request is being signed (see section 9.2.1) the
  Manifest Element of the Inquiry Request Signature Component should
  contain Digest elements of the Inquiry Type Component, and if
  present, the Payment Scheme Component.

7.19.8 Inquiry Response Signature Component

  If the Inquiry Response is being signed (see section 9.2.1) the
  Manifest Element of the Inquiry Response Signature Component should
  contain Digest elements of the Trading Response Block and the Status
  Component.

7.19.9 Ping Request Signature Component

  If the Ping Request is being singed (see section 9.2.2), the Manifest
  Element of the Ping Request Signature Component should contain Digest
  elements for all the Organisation Components.







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7.19.10 Ping Response Signature Component

  If the Ping Response is being singed (see section 9.2.2), the
  Manifest Element of the Ping Response Signature Component should
  contain Digest elements fir all the Organisation Components.

7.20 Certificate Component

  Note: Definitions of the XML structures for signatures and
  certificates are described in the paper "Digital Signatures for the
  Internet Open Trading Protocol", see [IOTPDSIG].

  See note at the start of section 7.19 Signature Component for more
  details.

  A Certificate Component contains a Digital Certificate. They are used
  only when required, for example, when asymmetric cryptography is
  being used and the recipient of the signature that needs to check has
  not already received the Public Key.

  The structure of a Certificate Component is defined in [IOTPDSIG].

7.20.1 IOTP usage of signature elements and attributes

  Detailed definitions of the above elements and attributes are
  contained in [IOTPDSIG]. The following contains additional
  information that describes how these elements and attributes are used
  by IOTP.

  CERTIFICATE COMPONENT

  The ID attribute is mandatory.

  VALUE ELEMENT

  The ID attribute is mandatory.

7.21 Error Component

  The Error Component contains information about Technical Errors (see
  section 4.1) in an IOTP Message which has been received by one of the
  Trading Roles involved in the trade.

  For clarity two phrases are defined which are used in the description
  of an Error Component:

  o  message in error. An IOTP message which contains or causes an
     error of some kind



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  o  message reporting the error. An IOTP message that contains an
     Error Component that describes the error found in a message in
     error.

  The definition of the Error Component is as follows.

  <!ELEMENT ErrorComp (ErrorLocation+, PackagedContent*) >
  <!ATTLIST ErrorComp
   ID                 NMTOKEN #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ErrorCode          NMTOKEN #REQUIRED
   ErrorDesc          CDATA   #REQUIRED
   Severity (Warning|TransientError|HardError) #REQUIRED
   MinRetrySecs       CDATA   #IMPLIED
   SwVendorErrorRef   CDATA   #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the Error
                     Component within the IOTP Transaction.

  xml:lang           Defines the language used by attributes or child
                     elements within this component, unless overridden
                     by an xml:lang attribute on a child element. See
                     section 3.8 Identifying Languages.

  ErrorCode          Contains an error code which indicates the nature
                     of the error in the message in error. Valid values
                     for the ErrorCode are given in section 7.21.2
                     Error Codes.

  ErrorDesc          Contains a narrative description of the error in
                     the language defined by xml:lang. The content of
                     this attribute is defined by the vendor/developer
                     of the software which generated the Error
                     Component

  Severity           Indicates the severity of the error.  Valid values
                     are:
                      o Warning. This indicates that although there is
                        a message in error the IOTP Transaction can
                        still continue.
                      o TransientError. This indicates that the error
                        in the message in error may be recovered if the
                        message in error  that is referred to by the
                        ErrorLocation element is resent





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                      o HardError. This indicates that there is an
                        unrecoverable error in the message in error and
                        the IOTP Transaction must stop.

  MinRetrySecs       This attribute should be present if Severity is
                     set to TransientError. It is the minimum number of
                     whole seconds which the IOTP aware application
                     which received the message reporting the error
                     should wait before re-sending the message in error
                     identified by the ErrorLocation element.

                     If Severity is not set to TransientError then the
                     value of this attribute is ignored.

  SwVendorErrorRef   This attribute is a reference whose value is set
                     by the vendor/developer of the software which
                     generated the Error Component. It should contain
                     data which enables the vendor to identify the
                     precise location in their software and the set of
                     circumstances which caused the software to
                     generate a message reporting the error. See also
                     the SoftwareId attribute of the Message Id element
                     in the Transaction Reference Block (section 3.3).

  Content:

  ErrorLocation      This identifies the IOTP Transaction Id of the
                     message in error  and, where possible, the element
                     and attribute in the message in error that caused
                     the Error Component to be generated.

                     If the Severity of the error is not
                     TransientError, more than one ErrorLocation may be
                     specified as appropriate depending on the nature
                     of the error (see section 7.21.2 Error Codes) and
                     at the discretion of  the vendor/developer of the
                     IOTP Aware Application.

  PackagedContent    This contains additional data which can be used to
                     understand the error. Its content may vary as
                     appropriate depending on the nature of the error
                     (see section 7.21.2 Error Codes) and at the
                     discretion of the vendor/developer of the IOTP
                     Aware Application. For a definition of
                     PackagedContent see section 3.7.






Burdett                      Informational                    [Page 156]

RFC 2801                       IOTP/1.0                       April 2000


7.21.1 Error Processing Guidelines

  If there is more than one Error Component in a message reporting the
  error, carry out the actions appropriate for the Error Component with
  the highest severity. In this context, HardError has a higher
  severity than TransientError, which has a higher severity than
  Warning.

7.21.1.1 Severity - Warning

  If an IOTP aware application is generating a message reporting the
  error with an Error Component where the Severity attribute is set to
  Warning, then if the message reporting the error does not contain
  another Error Component with a severity higher than Warning, the IOTP
  Message must also include the Trading Blocks and Trading Components
  that would have been included if no error was being reported.

  If a message reporting the error is received with an Error Component
  where Severity is set to Warning, then:

  o  it is recommended that information about the error is either
     logged, or otherwise reported to the user,

  o  the implementer of the IOTP aware application must either, at
     their or the user's discretion:

     -  continue the IOTP transaction as normal, or

     -  fail the IOTP transaction by generating a message reporting the
        error with an Error Component with Severity set to HardError
        (see section 7.21.1.3).

  If the intention is to continue the IOTP transaction then, if there
  are no other Error Components with a higher severity, check that the
  necessary Trading Blocks and Trading Components for normal processing
  of the transaction to continue are present. If they are not then
  generate a message reporting the error with an Error Component with
  Severity set to HardError.

7.21.1.2 Severity - Transient Error

  If an IOTP Aware Application is generating a message reporting the
  error with an Error Component where the Severity attribute is set to
  TransientError, then there should be only one Error Component in the
  message reporting the error. In addition, the MinRetrySecs attribute
  should be present.





Burdett                      Informational                    [Page 157]

RFC 2801                       IOTP/1.0                       April 2000


  If a message reporting the error is received with an Error Component
  where Severity is set to TransientError then:

  o  if the MinRetrySecs attribute is present and a valid number, then
     use the MinRetrySecs value given. Otherwise if MinRetrySecs is
     missing or is invalid, then:

     -  generate a message reporting the error containing an Error
        Component with a Severity of Warning and send it on the next
        IOTP message (if any) to be sent to the Trading Role which sent
        the message reporting the error with the invalid MinRetrySecs,
        and

     -  use a value for MinRetrySecs which is set by the
        vendor/developer of the IOTP Aware Application.

  o  check that only one ErrorLocation element is contained within the
     Error Component and that it refers to an IOTP Message which was
     sent by the recipient of the Error Component with a Severity of
     TransientError. If more than one ErrorLocation is present then
     generate a message reporting the error with a Severity of
     HardError.

7.21.1.3 Severity - Hard Error

  If an IOTP Aware Application is generating a message reporting the
  error with an Error Component where the Severity attribute set to
  HardError, then there should be only one Error Component in the
  message reporting the error.

  If a message reporting the error is received with an Error Component
  where Severity is set to HardError then terminate the IOTP
  Transaction.

7.21.2 Error Codes

  The following table contains the valid values for the ErrorCode
  attribute of the Error Component. The first sentence of the
  description contains the text that should be used to describe the
  error when displayed or otherwise reported. Individual
  implementations may translate this into alternative languages at
  their discretion.

  An Error Code must not be more that 14 characters long.







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       Value                           Description

  Reserved        Reserved. This error is reserved by the
                  vendor/developer of the software. Contact the
                  vendor/developer of the software for more information
                  See the SoftwareId attribute of the Message Id
                  element in the Transaction Reference Block(section
                  3.3).

  XmlNotWellFrmd  XML not well formed. The XML document is not well
                  formed. See [XML] for the meaning of "well formed".
                  Even if the XML is not well formed, it should still
                  be scanned to find the Transaction Reference Block so
                  that a properly formed Error Response may be
                  generated.

  XmlNotValid     XML not valid. The XML document is well formed but
                  the document is not valid. See [XML] for the meaning
                  of "valid". Specifically:
                   o the XML document does not comply with the
                    constraints defined in the IOTP document type
                    declaration (DTD) (see section 13 Internet Open
                    Trading Protocol Data Type Definition), and
                   o the XML document does not comply with the
                    constraints defined in the document type
                    declaration of any additional [XML Namespace] that
                    are declared.

                  As for XML not well formed, attempts should still be
                  made to extract the Transaction Reference Block so
                  that a properly formed Error Response may be
                  generated.

  ElUnexpected    Unexpected element. Although the XML document is well
                  formed and valid, an element is present that is not
                  expected in the particular context according to the
                  rules and constraints contained in this
                  specification.

  ElNotSupp       Element not supported. Although the document is well
                  formed and valid, an element is present that:
                   o is consistent with the rules and constraints
                    contained in this specification, but
                   o is not supported by the IOTP Aware Application
                    which is processing the IOTP Message.






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RFC 2801                       IOTP/1.0                       April 2000


  ElMissing       Element missing. Although the document is well formed
                  and valid, an element is missing that should have
                  been present if the rules and constraints contained
                  in this specification are followed.

                  In this case set the PackagedContent of the Error
                  Component to the type of the missing element.

  ElContIllegal   Element content illegal. Although the document is
                  well formed and valid, the element Content contains
                  values which do not conform to the rules and
                  constraints contained in this specification.

  EncapProtErr    Encapsulated protocol error. Although the document is
                  well formed and valid, the PackagedContent of an
                  element contains data from an encapsulated protocol
                  which contains errors.

  AttUnexpected   Unexpected attribute. Although the XML document is
                  well formed and valid, the presence of the attribute
                  is not expected in the particular context according
                  to the rules and constraints contained in this
                  specification.

  AttNotSupp      Attribute not supported. Although the XML document is
                  well formed and valid, and the presence of the
                  attribute in an element is consistent with the rules
                  and constraints contained in this specification, it
                  is not supported by the IOTP Aware Application which
                  is processing the IOTP Message.

  AttMissing      Attribute missing. Although the document is well
                  formed and valid, an attribute is missing that should
                  have been present if the rules and constraints
                  contained in this specification are followed.

                  In this case set the PackagedContent of the Error
                  Component to the type of the missing attribute.

  AttValIllegal   Attribute value illegal. The attribute contains a
                  value which does not conform to the rules and
                  constraints contained in this specification.

  AttValNotRecog  Attribute Value Not Recognised. The attribute
                  contains a value which the IOTP Aware Application
                  generating the message reporting the error could not
                  recognise.




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  MsgTooLarge     Message too large. The message is too large to be
                  processed by the IOTP Aware Application.

  ElTooLarge      Element too large. The element is too large to be
                  processed by the IOTP Aware Application

  ValueTooSmall   Value too small or early. The value of all or part of
                  the Content of an element or an attribute, although
                  valid, is too small.

  ValueTooLarge   Value too large or in the future. The value of all or
                  part of the Content of an element or an attribute,
                  although valid, is too large.

  ElInconsistent  Element Inconsistent. Although the document is well
                  formed and valid, according to the rules and
                  constraints contained in this specification:
                   o the content of an element is inconsistent with the
                    content of other elements or their attributes, or
                   o the value of an attribute is inconsistent with the
                    value of one or more other attributes.

                  In this case create ErrorLocation elements which
                  identify all the attributes or elements which are
                  inconsistent.

  TransportError  Transport Error. This error code is used to indicate
                  that there is a problem with the Transport Mechanism
                  which is preventing the message from being received.
                  It is typically associated with a Transient Error.
                  Explanation of the Transport Error is contained
                  within the ErrorDesc attribute. The values which can
                  be used inside ErrorDesc with a TransportError is
                  specified in the IOTP supplement for the Transport
                  mechanism.

  MsgBeingProc    Message Being Processed. This error code is only used
                  with a Severity of Transient Error. It indicates that
                  the previous message, which may be an exchange
                  message or a request message, is being processed and,
                  if no response is received by the time indicated by
                  the MinRetrySecs attribute, then the original message
                  should be resent.

  SystemBusy      System Busy. This error code is only used with a
                  Severity of Transient Error. It indicates that the
                  server that received a message is currently too busy
                  to handle the message. If no response is received by



Burdett                      Informational                    [Page 161]

RFC 2801                       IOTP/1.0                       April 2000


                  the time indicated by the MinRetrySecs attribute,
                  then the original message should be resent.

  Note: If the server/system handling the Transport Mechanism (e.g.,
  HTTP) is busy then a Transport Specific error message should be used
  instead of an IOTP Error message. This code should be used in
  association with IOTP servers/systems or other servers/systems to
  which the IOTP server is connected.

  UnknownError    Unknown Error. Indicates that the transaction cannot
                  complete for some reason that is not covered
                  explicitly by any of the other errors.  The ErrorDesc
                  attribute should be used to indicate the nature of
                  the problem.

                  This could be used to indicate, for example, an
                  internal error in a backend server or client process
                  of some kind.

7.21.3 Error Location Element

  An Error Location Element identifies an element and optionally an
  attribute in the message in error which is associated with the error.
  It contains a reference to the IOTP Message, Trading Block, Trading
  Component, element and attribute, which is in error.

  <!ELEMENT ErrorLocation EMPTY >
  <!ATTLIST ErrorLocation
   ElementType        NMTOKEN #REQUIRED
   IotpMsgRef         NMTOKEN #IMPLIED
   BlkRef             NMTOKEN #IMPLIED
   CompRef            NMTOKEN #IMPLIED
   ElementRef         NMTOKEN #IMPLIED
   AttName            NMTOKEN #IMPLIED >

  Attributes:

  ElementType        This is the name of the type of the element where
                     the error is located. For example if the element
                     was declared as <!ELEMENT Org ... then its name is
                     "Org".

  IotpMsgRef         This is the value of the ID attribute of the of
                     the Message Id Component (see section 3.3.2) of
                     the message in error to which this Error Component
                     applies.





Burdett                      Informational                    [Page 162]

RFC 2801                       IOTP/1.0                       April 2000


  BlkRef             If the error is associated with a specific Trading
                     Block, then this is the value of the ID attribute
                     of the Trading Block where the error is located.

  CompRef            If the error is associated with a specific Trading
                     Component, then this is the value of the ID
                     attribute of the Trading Component where the error
                     is located.

  ElementRef         If the error is associated with a specific element
                     within a Trading Component then, if the element
                     has an attribute with an "attribute type" (see
                     [XML]) of "ID", then this is the value of that
                     attribute.

  AttName            If the error is associated with the value of an
                     attribute, then this is the name of that
                     attribute. In this case the PackagedContent of the
                     Error Component should contain the value of the
                     attribute.

  Note that as many as the attributes as possible should be included.
  For example if an attribute in a child element of a Trading Component
  contains an incorrect value, then all the attributes of ErrorLocation
  should be present.

8. Trading Blocks

  Trading Blocks are child elements of the top level IOTP Messages that
  are sent in the form of [XML] documents directly between the
  different Trading Roles that are taking part in a trade.

  Each Trading Blocks consist of one or more Trading Components (see
  section 7).  This is illustrated in the diagram below.

















Burdett                      Informational                    [Page 163]

RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

            IOTP MESSAGE  <-----------IOTP Message - an XML Document
             |                        which is transported between the
             |                        Trading Roles
             |-Trans Ref Block <----- Trans Ref Block - contains
             |  |                     information which describes the
             |  |                     IOTP Transaction and the IOTP
             |  |                     Message.
             |  |-Trans Id Comp. <--- Transaction Id Component -
             |  |                     uniquely identifies the IOTP
             |  |                     Transaction. The Trans Id
             |  |                     Components are the same across
             |  |                     all IOTP messages that comprise a
             |  |                     single IOTP transaction.
             |  |-Msg Id Comp. <----- Message Id Component - identifies
             |                        and describes an IOTP Message
             |                        within an IOTP Transaction
             |-Signature Block <----- Signature Block (optional) -
             |  |                     contains one or more Signature
             |  |                     Components and their associated
             |  |                     Certificates
             |  |-Signature Comp. <-- Signature Component - contains
             |  |                     digital signatures. Signatures
             |  |                     may sign digests of the Trans Ref
             |  |                     Block and any Trading Component
             |  |                     in any IOTP Message in the same
             |  |                     IOTP Transaction.
             |  |-Certificate Comp. <-Certificate Component. Used to
             |                        check the signature. (Optional)
     ------> |-Trading Block <--------Trading Block - an XML Element
    |        |  |-Trading Comp.       within an IOTP Message that
  Trading    |  |-Trading Comp.       contains a predefined set of
  Blocks     |  |-Trading Comp.       Trading Components
    |        |  |-Trading Comp.
    |        |  |-Trading Comp. <-----Trading Components - XML Elements
    |        |                        within a Trading Block that
     ------> |-Trading Block          contain a predefined set of XML
             |  |-Trading Comp.       elements and attributes
             |  |-Trading Comp.       containing information required
             |  |-Trading Comp.       to support a Trading Exchange
             |  |-Trading Comp.
             |  |-Trading Comp.
             |
  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                           Figure 16 Trading Blocks




Burdett                      Informational                    [Page 164]

RFC 2801                       IOTP/1.0                       April 2000


  Trading Blocks are defined as part of the definition of an IOTP
  Message (see section 3.1.1). The definition of an IOTP Message
  element is repeated here:

  <!ELEMENT IotpMessage
     ( TransRefBlk,
       SigBlk?,
       ErrorBlk?,
       ( AuthReqBlk |
         AuthRespBlk |
         AuthStatusBlk |
         CancelBlk |
         DeliveryReqBlk |
         DeliveryRespBlk |
         InquiryReqBlk |
         InquiryRespBlk |
         OfferRespBlk |
         PayExchBlk |
         PayReqBlk |
         PayRespBlk |
         PingReqBlk |
         PingRespBlk |
         TpoBlk |
         TpoSelectionBlk
       )*
     ) >

  The remainder of this section defines the Trading Blocks in this
  version of IOTP. They are:

  o  Authentication Request Block

  o  Authentication Response Block

  o  Authentication Status Block

  o  Cancel Block

  o  Delivery Request Block

  o  Delivery Response Block

  o  Error Block

  o  Inquiry Request Block

  o  Inquiry Response Block




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  o  Offer Response Block

  o  Payment Exchange Block

  o  Payment Request Block

  o  Payment Response Block

  o  Signature Block

  o  Trading Protocol Options Block

  o  TPO Selection Block

  The Transaction Reference Block is described in section 3.3.

8.1 Trading Protocol Options Block

  The TPO Trading Block contains options which apply to the IOTP
  Transaction. The definition of a TPO Trading Block is as follows.

  <!ELEMENT TpoBlk ( ProtocolOptions, BrandList*, Org* ) >
  <!ATTLIST TpoBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Trading Protocol Options Block within the IOTP
                     Transaction (see section 3.4 ID Attributes).

  Content:

  ProtocolOptions    The Protocol Options Component (see section
                     7.1)defines the options which apply to the whole
                     IOTP Transaction (see section 9).

  BrandList          This Brand List Component contains one or more
                     payment brands and protocols which may be selected
                     (see section 7.7).

  Org                The Organisation Components (see section 7.6)
                     identify the Organisations and their roles in the
                     IOTP Transaction. The roles and Organisations
                     which must be present will depend on the
                     particular type of IOTP Transaction. See the
                     definition of each transaction in section 9.
                     Internet Open Trading Protocol Transactions.



Burdett                      Informational                    [Page 166]

RFC 2801                       IOTP/1.0                       April 2000


  The TPO Block should contain:

  o  the Protocol Options Component

  o  the Organisation Component with the Trading Role of Merchant

  o  the Organisation Component with the Trading Role of Consumer

  o  optionally, the Organisation Component with the Trading Role of
     DeliverTo, if there is a Delivery included in the IOTP Transaction

  o  Brand List Components for each payment in the IOTP Transaction

  o  Organisation Components for all the Payment Handlers involved

  o  optionally, Organisation Components for the Delivery Handler (if
     any) for the transaction

  o  additional Organisation Components that the Merchant may want to
     include. For example

     -  a Customer Care Provider

     -  an Certificate Authority that offers Merchant "Credentials" or
        some other warranty on the goods or services being offered.

8.2 TPO Selection Block

  The TPO Selection Block contains the results of selections made from
  the options contained in the Trading Protocol Options Block (see
  section 8.1).The definition of a TPO Selection Block is as follows.

  <!ELEMENT TpoSelectionBlk (BrandSelection+) >
  <!ATTLIST TpoSelectionBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the TPO
                     Selection Block within the IOTP Transaction.

  Content:

  BrandSelection     This identifies the choice of payment brand and
                     payment protocol to be used in a payment within
                     the IOTP Transaction. There is one Brand Selection
                     Component (see section 7.8) for each payment to be
                     made in the IOTP Transaction.



Burdett                      Informational                    [Page 167]

RFC 2801                       IOTP/1.0                       April 2000


  The TPO Selection Block should contain one Brand Selection Component
  for each Brand List in the TPO Block.

8.3 Offer Response Block

  The Offer Response Block contains details of the goods, services,
  amount, delivery instructions or financial transaction which is to
  take place.  Its definition is as follows.

  <!ELEMENT OfferRespBlk (Status, Order?, Payment*,
               Delivery?, TradingRoleData*) >
  <!ATTLIST OfferRespBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the Offer
                     Response Block within the IOTP Transaction.

  Content:

  Status             Contains status information about the business
                     success (see section 4.2) or failure of the
                     generation of the Offer. Note that in an Offer
                     Response Block, a ProcessState of NotYetStarted or
                     InProgress are illegal values.

  Order              The Order Component contains details about the
                     goods, services or financial transaction which is
                     taking place see section 7.5.

                     The Order Component must be present unless the
                     ProcessState attribute of the Status Component is
                     set to Failed.

  Payment            The Payment Components contain information about
                     the payments which are to be made see section 7.9.

  Delivery           The Delivery Component contains details of the
                     delivery to be made (see section 7.13).

  TradingRoleData    The Trading Role Data Component contains opaque
                     data which is needs to be communicated between the
                     Trading Roles involved in an IOTP Transaction (see
                     section 7.17).

  The Offer Response Block should contain:




Burdett                      Informational                    [Page 168]

RFC 2801                       IOTP/1.0                       April 2000


  o  the Order Component for the IOTP Transaction

  o  Payment Components for each Payment in the IOTP Transaction

  o  the Delivery Component the IOTP Transaction requires (if any).

8.4 Authentication Request Block

  The Authentication Request Block contains the data which is used by
  one Trading Role to obtain information about and optionally
  authenticate another Trading Role.

  In outline it contains:

  o  information about how the authentication itself will be carried
     out, and/or

  o  a request for additional information about the Organisation being
     authenticated.

  Its definition is as follows.

  <!ELEMENT AuthReqBlk (AuthReq*, TradingRoleInfoReq?) >
  <!ATTLIST AuthReqBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Authentication Request Block within the IOTP
                     Transaction.

  Content:

  AuthReq             Each Authentication Request (see section 7.2)
                      component describes an alternative way in which
                      the recipient of the Authentication Request may
                      authenticate themselves by generating an
                      Authentication Response Component (see section
                      7.3).

                      If one Authentication Request Component is
                      present then that Authentication Request
                      Component should be used.







Burdett                      Informational                    [Page 169]

RFC 2801                       IOTP/1.0                       April 2000


                      If more than one Authentication Request Component
                      is present then the recipient should choose one
                      of the components based on personal preference of
                      the recipient or their software.

                      If no Authentication Request Component is present
                      it means that the Authentication Request Block is
                      requesting the return of Organisation Components
                      as specified in the Trading Role Information
                      Request Component.

  TradingRoleInfoReq  The Trading Role Information Request Component
                      (see section 7.4) contains a list of Trading
                      Roles about which information is being requested

  There must be at least one Component (either an Authentication
  Request or a Trading Role Information Request) within the
  Authentication Block otherwise it is an error.

8.5 Authentication Response Block

  The Authentication Response Block contains the response which results
  from processing the Authentication Request Block. Its definition is
  as follows.

  <!ELEMENT AuthRespBlk (AuthResp?, Org*) >
  <!ATTLIST AuthRespBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Authentication Response Block within the IOTP
                     Transaction.

  Content:

  AuthResp           The optional Authentication Response Component
                     which contains the results of processing the
                     Authentication Request Component - see section
                     7.3.

  Org                Optional Organisation Components that contain
                     information corresponding to the Trading Roles as
                     requested by the TradingRoleList attribute of the
                     Trading Role Information Request component.





Burdett                      Informational                    [Page 170]

RFC 2801                       IOTP/1.0                       April 2000


  The components present in the Authentication Response Block must
  match the requirement of the corresponding Authentication Request
  Block otherwise it is an error.

8.6 Authentication Status Block

  The Authentication Status Block indicates the success or failure of
  the validation of an Authentication Response Block by an
  Authenticator. Its definition is as follows.

  <!ELEMENT AuthStatusBlk (Status) >
  <!ATTLIST AuthStatusBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Authentication Status Block within the IOTP
                     Transaction.

  Content:

  Status             Contains status information about the business
                     success (see section 4.2) or failure of the
                     authentication

8.7 Payment Request Block

  The Payment Request Block contains information which requests that a
  payment is started. Its definition is as follows.

  <!ELEMENT PayReqBlk (Status+, BrandList, BrandSelection,
       Payment, PaySchemeData?, Org*, TradingRoleData*) >
  <!ATTLIST PayReqBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Payment Request Block within the IOTP Transaction.

  Content:

  Status             Contains the Status Components (see section 7.13)
                     of the responses of the steps (e.g., an Offer
                     Response and/or a Payment Response) on which this





Burdett                      Informational                    [Page 171]

RFC 2801                       IOTP/1.0                       April 2000


                     step depends. It is used to indicate the success
                     or failure of those steps. Payment should only
                     occur if the previous steps were successful.

  BrandList          The Brand List Component contains a list of one or
                     more payment brands and protocols which may be
                     selected (see section 7.7).

  BrandSelection     This identifies the choice of payment brand, the
                     payment protocol and the Payment Handler to be
                     used in a payment within the IOTP Transaction.
                     There is one Brand Selection Component (see
                     section 7.8) for each payment to be made in the
                     IOTP Transaction.

  Payment            The Payment Components contain information about
                     the payment which is being made see section 7.9.

  PaySchemeData      The Payment Scheme Component contains payment
                     scheme specific data see section 7.10.

  Org                The Organisation Component contains details of
                     Organisations involved in the payment (see section
                     7.6). The Organisations present are dependent on
                     the IOTP Transaction and the data which is to be
                     signed. See section 6 Digital Signatures for more
                     details.

  TradingRoleData    The Trading Role Data Component contains opaque
                     data which is needs to be communicated between the
                     Trading Roles involved in an IOTP Transaction (see
                     section 7.17).

  The Payment Request Block should contain:

  o  the Organisation Component with a Trading Role of Merchant

  o  the Organisation Component with the Trading Role of Consumer

  o  the Payment Component for the Payment

  o  the Brand List Component for the Payment

  o  the Brand Selection Component for the Brand List

  o  the Organisation Component for the Payment Handler of the Payment





Burdett                      Informational                    [Page 172]

RFC 2801                       IOTP/1.0                       April 2000


  o  the Organisation Component (if any) for the Organisation which
     carried out the previous step, for example another Payment Handler

  o  the Organisation Component for the Organisation which is to carry
     out the next step, if any. This may be, for example, either a
     Delivery Handler or a Payment Handler.

  o  the Organisation Components for any additional Organisations that
     the Merchant has included in the Offer Response Block

  o  an Optional Payment Scheme Data Component, if required by the
     Payment Method as defined in the IOTP supplement for the payment
     method

  o  any Trading Role Data Components that may be required (see section
     7.17.1).

8.8 Payment Exchange Block

  The Payment Exchange Block contains payment scheme specific data
  which is exchanged between two of the roles in a trade. Its
  definition is as follows.

  <!ELEMENT PayExchBlk (PaySchemeData+) >
  <!ATTLIST PayExchBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Payment Exchange Block within the IOTP
                     Transaction.

  Content:

  PaySchemeData      This Trading Component contains payment scheme
                     specific data see section 7.10 Payment Scheme
                     Component.

8.9 Payment Response Block

  This Payment Response Block contains a information about the Payment
  Status, an optional Payment Receipt, and an optional payment protocol
  message. Its definition is as follows.







Burdett                      Informational                    [Page 173]

RFC 2801                       IOTP/1.0                       April 2000


  <!ELEMENT PayRespBlk (Status, PayReceipt?, PaySchemeData?,
       PaymentNote?, TradingRoleData*) >
  <!ATTLIST PayRespBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Payment Response Block within the IOTP
                     Transaction.

  Content:

  Status             Contains status information about the business
                     success (see section 4.2) or failure of the
                     payment. Note that in a Pay Response Block, a
                     ProcessState of NotYetStarted or InProgress are
                     illegal values.

  PayReceipt         Contains payment scheme specific data which can be
                     used to verify the payment occurred. See section
                     7.11 Payment Receipt Component. It must be present
                     if the ProcessState attribute of the Status
                     Component is set to CompletedOk. PayReceipt is
                     optional for other values as specified by the
                     appropriate Payment Scheme supplement.

  PaySchemeData      Contains payment scheme specific data see section,
                     for example a payment protocol message. See 7.10
                     Payment Scheme Component.

  PaymentNote        Contains additional, non payment related,
                     information which the Payment Handler wants to
                     provide to the Consumer. For example, if a
                     withdrawal or deposit were being made then it
                     could contain information on the remaining balance
                     on the account after the transfer was complete.
                     See section 7.12 Payment Note Component.

  TradingRoleData    The Trading Role Data Component contains opaque
                     data which is needs to be communicated between the
                     Trading Roles involved in an IOTP Transaction (see
                     section 7.17).








Burdett                      Informational                    [Page 174]

RFC 2801                       IOTP/1.0                       April 2000


8.10 Delivery Request Block

  The Delivery Request Block contains details of the goods or services
  which are to be delivered together with a signature which can be used
  to check that delivery is authorised. Its definition is as follows.

  <!ELEMENT DeliveryReqBlk (Status+, Order, Org*, Delivery,
       ConsumerDeliveryData?, TradingRoleData*) >
  <!ATTLIST DeliveryReqBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Delivery Request Block within the IOTP
                     Transaction.

  Content:

  Status                Contains the Status Components (see section
                        7.13) of the responses of the steps (e.g., a
                        Payment Response) on which this step is
                        dependent. It is used to indicate the success
                        or failure of those steps. Delivery should only
                        occur if the previous steps were successful.

  Order                 The Order Component contains details about the
                        goods, services or financial transaction which
                        is taking place see section 7.5.

                        The Organisation Components (see section 7.6)
                        identify the Organisations and their roles in
  Org                   the IOTP Transaction. The roles and
                        Organisations which must be present will depend
                        on the particular type of IOTP Transaction. See
                        the definition of each transaction in section
                        9. Internet Open Trading Protocol Transactions.

  Delivery              The Delivery Component contains details of the
                        delivery to be made (see section 7.13).

  ConsumerDeliveryData  Optional. Contains an identifier specified by
                        the Consumer which, if returned by the Delivery
                        Handler will enable the Consumer to identify
                        which Delivery is being referred to.






Burdett                      Informational                    [Page 175]

RFC 2801                       IOTP/1.0                       April 2000


  TradingRoleData       The Trading Role Data Component contains opaque
                        data which is needs to be communicated between
                        the Trading Roles involved in an IOTP
                        Transaction (see section 7.17).

  The Delivery Request Block contains:

  o  the Organisation Component with a Trading Role of Merchant

  o  the Organisation Component for the Consumer and DeliverTo Trading
     Roles

  o  the Delivery Component for the Delivery

  o  the Organisation Component for the Delivery Handler. Specifically
     the Organisation Component identified by the ActionOrgRef
     attribute on the Delivery Component

  o  the Organisation Component (if any) for the Organisation which
     carried out the previous step, for example a Payment Handler

  o  the Organisation Components for any additional Organisations that
     the Merchant has included in the Offer Response Block

  o  any Trading Role Data Components that may be required (see section
     7.17.1).

8.11 Delivery Response Block

  The Delivery Response Block contains a Delivery Note containing
  details on how the goods will be delivered. Its definition is as
  follows. Note that in a Delivery Response Block a Delivery Status
  Element with a DeliveryStatusCode of NotYetStarted or InProgress is
  invalid.

  <!ELEMENT DeliveryRespBlk (Status, DeliveryNote) >
  <!ATTLIST DeliveryRespBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Delivery Response Block within the IOTP
                     Transaction.

  Content:





Burdett                      Informational                    [Page 176]

RFC 2801                       IOTP/1.0                       April 2000


  Status             Contains status information about the business
                     success (see section 4.2) or failure of the
                     delivery.  Note that in a Delivery Response Block,
                     a ProcessState of NotYetStarted or InProgress are
                     illegal values.

  DeliveryNote       The Delivery Note Component contains details about
                     how the goods or services will be delivered (see
                     section 7.15).

8.12 Inquiry Request Trading Block

  The Inquiry Request Trading Block contains an Inquiry Type Component
  and an optional Payment Scheme Component to contain payment scheme
  specific inquiry messages.

  <!ELEMENT InquiryReqBlk ( InquiryType, PaySchemeData? ) >
  <!ATTLIST InquiryReqBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Inquiry Request Trading Block within the IOTP
                     Transaction.

  Content:

  InquiryType        Inquiry Type Component (see section 7.18) that
                     contains the type of inquiry.

  PaySchemeData      Payment Scheme Component (see section 7.10) that
                     contains payment scheme specific inquiry messages
                     for inquiries on payments. This is present when
                     the Type attribute of Inquiry Type Component is
                     Payment.

8.13 Inquiry Response Trading Block

  The Inquiry Response Trading Block contains a Status Component and an
  optional Payment Scheme Component to contain payment scheme specific
  inquiry messages. Its purpose is to enquire on the current status of
  an IOTP transaction at a server.








Burdett                      Informational                    [Page 177]

RFC 2801                       IOTP/1.0                       April 2000


  <!ELEMENT InquiryRespBlk (Status, PaySchemeData?) >
  <!ATTLIST InquiryRespBlk
   ID                 ID      #REQUIRED
   LastReceivedIotpMsgRef NMTOKEN #IMPLIED
   LastSentIotpMsgRef  NMTOKEN #IMPLIED >

  Attributes:

  ID                      An identifier which uniquely identifies the
                          Inquiry Response Trading Block within the
                          IOTP Transaction.

  LastReceivedIotpMsgRef  Contains an Element Reference (see section
                          3.5) to the Message Id Component (see section
                          3.3.2) of the last message this server has
                          received from the Consumer. If there is no
                          previously received message from the Consumer
                          in the pertinent transaction, this attribute
                          should be contain the value Null. This
                          attribute exists for debugging purposes.

  LastSentIotpMsgRef      Contains an Element Reference (see section
                          3.5) to the Message Id Component (see section
                          3.3.2) of the last message this server has
                          sent to the Consumer. If there is no
                          previously sent message to the Consumer in
                          the pertinent transaction, this attribute
                          should contain the value Null. This attribute
                          exists for debugging purposes.

  Content:

  Status             Contains status information about the business
                     success (see section 4.2) or failure of a certain
                     trading exchange (i.e., Offer, Payment, or
                     Delivery).

  PaySchemeData      Payment Scheme Component (see section 7.10) that
                     contains payment scheme specific inquiry messages
                     for inquiries on payments. This is present when
                     the Type attribute of StatusType attribute of the
                     Status Component is set to Payment.









Burdett                      Informational                    [Page 178]

RFC 2801                       IOTP/1.0                       April 2000


8.14 Ping Request Block

  The Ping Request Block is used to determine if a Server is operating
  and whether or not cryptography is compatible.

  The definition of a Ping Request Block is as follows.

  <!ELEMENT PingReqBlk (Org*)>
  <!ATTLIST PingReqBlk
   ID                 ID      #REQUIRED>

  Attributes:

  ID                 An identifier which uniquely identifies the Ping
                     Request Trading Block within the IOTP Transaction.

  Content:

  Org                Optional Organisation Components (see section
                     7.6).

                     If no Organisation Component is present then the
                     Ping Request is anonymous and simply determines if
                     the server is operating.

                     However if Organisation Components are present,
                     then it indicates that the sender of the Ping
                     Request wants to verify that digital signatures
                     can be handled.

                     In this case the sender includes:
                      o an Organisation Component that identifies
                        itself specifying the Trading Role(s) it is
                        taking in IOTP transactions (Merchant, Payment
                        Handler, etc.)
                      o an Organisation Component that identifies the
                        intended recipient of the message.

                     These are then used to generate a signature over
                     the Ping Response Block.

8.15 Ping Response Block

  The Ping Response Trading Block provides the result of a Ping
  Request.

  It contains an Organisation Component that identifies the sender of
  the Ping Response.



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  If the Ping Request to which this block is a response contained
  Organisation Components, then it also contains those Organisation
  Components.

  <!ELEMENT PingRespBlk (Org+)>
  <!ATTLIST PingRespBlk
   ID                 ID      #REQUIRED
   PingStatusCode (Ok | Busy | Down) #REQUIRED
   SigVerifyStatusCode (Ok | NotSupported | Fail) #IMPLIED
   xml:lang           NMTOKEN #IMPLIED
   PingStatusDesc     CDATA   #IMPLIED>

  Attributes:

  ID                   An identifier which uniquely identifies the Ping
                       Request Trading Block within the IOTP
                       Transaction.

  PingStatusCode       Contains a code which shows the status of the
                       sender software which processes IOTP messages.
                       Valid values are:
                        o Ok. Everything with the service is working
                         normally, including the signature
                         verification.
                        o Busy. Things are working normally but there
                         may be some delays.
                        o Down. The server is not functioning fully but
                         can still provide a Ping response.

  SigVerifyStatusCode  Contains a code which shows the status of
                       signature verification. This is present only
                       when the message containing the Ping Request
                       Block also contains a Signature Block. Valid
                       values are:
                        o Ok. The signature has successfully been
                         verified and proved compatible.
                        o NotSupported The receiver of this Ping
                         Request Block does not support validation of
                         signatures.
                        o Fail. Signature verification failed.

  Xml:lang             Defines the language used in PingStatusDesc.
                       This is present when PingStatusDesc is present.

  PingStatusDesc       Contains a short description of the status of
                       the server which sends this Ping Response Block.
                       Servers, if their designers want, can use this




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                       attribute to send more refined status
                       information than PingStatusCode which can be
                       used for debugging purposes, for example.

  Content:

  Org                These are Organisation Components (see section
                     7.6).

                     The Organisation Components of the sender of the
                     Ping Response is always included in addition to
                     the Organisation Components sent in the Ping
                     Request.

  Note: Ping Status Code values do not include a value such as Fail,
  since, when the software receiving the Ping Request message is not
  working at all, no Ping Response message will be sent back.

8.16 Signature Block

  The Signature Block contains one or more Signature Components and
  associated Certificates (if required) which sign data associated with
  the IOTP Transaction. For a general discussion and introduction to
  how IOTP uses signatures, see section 6 Digital Signatures. The
  definition of the Signature Component and certificates is contained
  in the paper "Digital Signatures for the Internet Open Trading
  Protocol", see [IOTPDSIG].  Descriptions of how these are used by
  IOTP is contained in sections 7.19 and 7.20.

  The definition of a Signature Block is as follows:

  <!ELEMENT IotpSignatures (Signature+, Certificate*) >
  <!ATTLIST IotpSignatures
    ID                ID      #IMPLIED >

  Attributes:

  ID                 An identifier which uniquely identifies the
                     Signature Block within the IOTP Transaction.

  Content:

  Signature          A Signature Component. See section 7.19.

  Certificate        A Certificate Component. See section 7.20.






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  The contents of a Signature Block depends on the Trading Block that
  is contained in the same IOTP Message as the Signature Block.

8.16.1 Signature Block with Offer Response

  A Signature Block which is in the same message as an Offer Response
  Block contains just an Offer Response Signature Component (see
  section 7.19.2).

8.16.2 Signature Block with Payment Request

  A Signature Block which is in the same message as a Payment Request
  Block contains:

  o  an Offer Response Signature Component (see section 7.19.2), and

  o  if the Payment is dependent on an earlier step (as indicated by
     the StartAfter attribute on the Payment Component), then the
     Payment Receipt Signature Component (see section 7.19.3) generated
     by the previous step

8.16.3 Signature Block with Payment Response

     A Signature Block which is in the same message as a Payment
     Response Block contains just a Payment Receipt Signature Component
     (see section 7.19.3) generated by the step.

8.16.4 Signature Block with Delivery Request

     A Signature Block which is in the same message as a Delivery
     Request Block contains:

  o  an Offer Response Signature Component (see section 7.19.2), and

  o  the Payment Receipt Signature Component (see section 7.19.3)
     generated by the previous step.

8.16.5 Signature Block with Delivery Response

  A Signature Block which is in the same message as a Delivery Response
  Block contains just a Delivery Response Signature component (see
  section 7.19.4) generated by the step.









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RFC 2801                       IOTP/1.0                       April 2000


8.17 Error Block

  The Error Trading Block contains one or more Error Components (see
  section 7.21) which contain information about Technical Errors (see
  section 4.1) in an IOTP Message which has been received by one of the
  Trading Roles involved in the trade.

  For clarity two phrases are defined which are used in the description
  of an Error Trading Block:

  o  message in error. An IOTP message which contains or causes an
     error of some kind

  o  message reporting the error. An IOTP message that contains an
     Error Trading Block that describes the error found in a message in
     error.

  An Error Trading Block may be contained in any message reporting the
  error. The action which then follows depends on the severity of the
  error. See the definition of an Error Component, for an explanation
  of the different types of severity and the actions which can then
  occur.

  in3 Note: Although, an Error Trading Block can report multiple
  different errors using multiple Error Components, there is no
  obligation on a developer of an IOTP Aware Application to do so.

  The structure of an Error Trading Block is as follows.

  <!ELEMENT ErrorBlk (ErrorComp+, PaySchemeData*) >
  <!ATTLIST ErrorBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the Error
                     Trading Block within the IOTP Transaction.

  Content:

  ErrorComp          An Error Components (see section 7.21) that
                     contains information about an individual Technical
                     Error.

  PaySchemeData      An optional Payment Scheme Component (see section
                     7.10) which contains a Payment Scheme Message. See
                     the appropriate payment scheme supplement to




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                     determine whether or not this component needs to
                     be present and for the definition of what it must
                     contain.

8.18 Cancel Block

  The Cancel Block is used by one Trading Role to inform any other that
  a transaction has been cancelled. Example usage includes:

  o  a Consumer Role informing a non-Consumer role that it no longer
     plans to continue with the transaction. This will allow the server
     to close down the transaction tidily without a waiting for a
     time-out to occur

  o  a non-Consumer Role to inform a Consumer role that the Transaction
     is being stopped. In this case, the Consumer is then unlikely to
     re-send the previous message that was sent in the mistaken
     understanding that the original was not received.

  Its definition is as follows.

  <!ELEMENT CancelBlk (Status) >
  <!ATTLIST CancelBlk
   ID                 ID      #REQUIRED >

  Attributes:

  ID                 An identifier which uniquely identifies the Cancel
                     Block within the IOTP Transaction.

  Content:

  Status             Contains status information indicating that the
                     IOTP transaction has been cancelled.

9. Internet Open Trading Protocol Transactions

  The Baseline Internet Open Trading Protocol supports three types of
  transactions for different purposes. These are

  o  an Authentication IOTP transaction which supports authentication
     of one party in a trade by another and/or requests information
     about another Trading Role








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  o  IOTP Transactions that involve one or more payments. Specifically:

     -  Deposit

     -  Purchase

     -  Refund

     -  Withdrawal, and

     -  Value Exchange

  o  IOTP Transactions designed to check the correct function of the
     IOTP infrastructure. Specifically:

     -  Transaction Status Inquiry, and

     -  Ping

  Although the Authentication IOTP Transaction can operate on its own,
  authentication can optionally precede any of the "payment"
  transactions.  Therefore, the rest of this section is divided into
  two parts covering:

  o  Authentication and Payment transactions (Authentication, Deposit,
     Purchase, Refund, Withdrawal and Value Exchange)

  o  Infrastructure Transactions (Transaction Status Inquiry and Ping)
     that are designed to support inquiries on whether or not a
     transaction has succeeded or a Trading Role's servers are
     operating correctly, and

9.1 Authentication and Payment Related IOTP Transactions

     The Authentication and Payment related IOTP Transactions consist
     of six Document Exchanges which are then combined in sequence to
     implement a specific transaction.

     Generally, there is a close, but not exact, correspondence between
     a Document Exchange and a Trading Exchange. The main difference is
     that some Document Exchanges implement part or all of two Trading
     Exchanges simultaneously in order to minimise the number of actual
     IOTP Messages which must be sent over the Internet.

     The six Document Exchanges are:

  o  Authentication. This is a direct implementation of the
     Authentication Trading Exchange



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  o  Brand Dependent Offer. This is the Offer Trading Exchange combined
     with the Brand Selection part of the Payment Trading Exchange. Its
     purpose is to provide the Merchant with information on the Brand
     selected so that the content of the Offer Response may be adapted
     accordingly

  o  Brand Independent Offer. This is also an Offer Trading Exchange.
     However, in this instance, the content of the Offer Response does
     not depend on the Brand selected.

  o  Payment. This is a direct implementation of the Payment part of a
     Payment Trading Exchange

  o  Delivery. This is a direct implementation of the Delivery Exchange

  o  Delivery with Payment. This is an implementation of combined
     Payment and Delivery Trading Exchanges

  These Document Exchanges are combined together in different sequences
  to implement each IOTP Transaction. The way in which they may be
  combined is illustrated by the diagram below.






























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RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

    START -----------------------------------------------------
     |                                                         v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |    |
                      |                     |              |    |
                      |      -------------- | -------------     |
                      v      v              v      v            |
                 -------------------     -----------------      |
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
                |       OFFER       |   |      OFFER      |     |
                 -------------------     -----------------      |
                       |    |                   |   |           |
                       |     ---------------    |   |           |
                       |                    |   |   |           |
                       |     -------------- | --    |           |
                       v    v               v       v           |
                     ---------           --------------         |
                    | PAYMENT |         | PAYMENT WITH |        |
                    | (first) |         |   DELIVERY   |        |
                     ---------           --------------         |
                         |                      |               |
             -----------------------------      |               |
             v                v           |     |               |
        ----------        ---------       |     |               |
       | DELIVERY |      | PAYMENT |      |     |               |
       |          |      | {second)|      |     |               |
        ----------        ---------       |     |               |
             |                |           |     |               v
              ----------------------------------------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

        Figure 17 Payment and Authentication Message Flow Combinations

  The combinations of Document Exchanges that are valid depend on the
  particular IOTP transaction.

  The remainder of this sub-section describes:

  o  each Document Exchange in more detail including descriptions of
     the content of each Trading Block in the Document Exchanges, and

  o  descriptions of how each IOTP Transaction uses the Document
     Exchanges to effect the desired result.



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RFC 2801                       IOTP/1.0                       April 2000


  Note: The descriptions of the Document Exchanges which follow
  describe the ways in which various Business Errors (see section 4.2)
  are handled. No reference is made however to the handling of
  Technical Errors (see section 4.1) in any of the messages since these
  are handled the same way irrespective of the context in which the
  message is being sent. See section 4 for more details.

9.1.1 Authentication Document Exchange

  The Authentication Document Exchange is a direct implementation of
  the Authentication Trading Exchange (see section 2.2.4). It involves:

  o  an Authenticator - the Organisation which is requesting the
     authentication, and

  o  an Authenticatee - the Organisation being authenticated.

  The authentication consists of:

  o  an Authentication Request being sent by the Authenticator to the
     Authenticatee,

  o  an Authentication Response being sent in return by the
     Authenticatee to the Authenticator which is then checked, and

  o  an Authentication Status being sent by the Authenticator to the
     Authenticatee to provide an indication of the success or failure
     of the authentication.

  An Authentication Document Exchange also:

  o  provides an Authenticatee with an Organisation Component which
     describes the Authenticator, and

  o  optionally provides the Authenticator with Organisation Components
     which describe the Authenticatee.

  The Authentication Request may also be digitally signed which allows
  the Authenticatee to verify the credentials of the Authenticator.

  The IOTP Messages which are involved are illustrated by the diagram
  below.









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RFC 2801                       IOTP/1.0                       April 2000


*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
Organisation 1
(Authenticatee)
    |   Organisation 2
    |  (Authenticator)
STEP |     |
1.          First Organisation takes an action (for example by
            pressing a button on an HTML page) which requires that
            the Organisation is authenticated

    1 --> 2 Authentication Need (outside scope of IOTP)

2.          The second Organisation generates: an Authentication
            Request Block containing one or more Authentication
            Request Components and/or a Trading Role Information
            Request Component, then sends it to the first
            Organisation

    1 <-- 2 TPO & AUTHENTICATION REQUEST. IotpMsg: Trans Ref Block;
            Signature Block (optional); TPO Block; Auth Request Block

3.          IOTP aware application started. If a Signature Block is
            present, the first Organisation may use this to check the
            credentials of the second Organisation. If credentials are
            OK, the first Organisation selects an Authentication
            Request to use (if present and more than one), then uses
            the authentication algorithm selected to generate an
            Authentication Response Block. If present, the Trading
            Role Information Request Component is used to generate
            Organisation Components. Finally a Signature Component is
            created if required and all components are then sent back
            to the second Organisation for validation.

    1 --> 2 AUTHENTICATION RESPONSE. IotpMsg; Trans Ref Block;
            Signature Block (optional) ; Auth Response Block

4.          The second Organisation checks the Authentication
            Response against the data in the Authentication Request
            Block to check that the first Organisation is who they
            appear to be, and sends an Authentication Status Block to
            the first Organisation to indicate the result then
            stops.

    1 <-- 2 AUTHENTICATION STATUS. IotpMsg: Trans Ref Block;
            Signature Block (optional); Auth Response Block






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5.          The first Organisation checks the authentication Status
            Block and optionally keeps information on the IOTP
            transaction for record keeping purposes and stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                Figure 18 Authentication Document Exchange

9.1.1.1 Message Processing Guidelines

  On receiving a TPO & Authentication Request IOTP Message (see below),
  an Authenticatee may either:

  o  generate and send an Authentication Response IOTP Message back to
     the Authenticator, or

  o  indicate failure to comply with the Authentication Request by
     sending a Cancel Block back to the Authenticator containing a
     Status Component with a StatusType of Authentication a
     ProcessState of Failed and the CompletionCode (see section 7.16.4)
     set to either: AutEeCancel, NoAuthReq, TradRolesIncon or
     Unspecified.

  On receiving an Authentication Response IOTP Message (see below), an
  Authenticator should send in return, an Authentication Status IOTP
  Message (see below) containing a Status Block with a Status Component
  where the StatusType is set to Authentication, and:

  o  the ProcessState attribute of the Status Component is set to
     CompletedOk which indicates a successful completion, or

  o  the ProcessState attribute is set to Failed and the CompletionCode
     attribute is set to either: AutOrCancel, AuthFailed or Unspecified
     which indicates a failed authentication,

  On receiving an Authentication Status IOTP Message (see below), the
  Authenticatee should check the Status Component in the Status Block.
  If this indicates:

  o  a successful authentication, then the Authenticatee should either:

     -  continue with the next step in the IOTP Transaction of which
        the Authentication Document Exchange is part (if any), or








Burdett                      Informational                    [Page 190]

RFC 2801                       IOTP/1.0                       April 2000


     -  indicate a failure to continue with the rest of the IOTP
        Transaction, by sending back to the Authenticator a Cancel
        Block containing a Status Component with a StatusType of
        Authentication, a ProcessState of Failed and the CompletionCode
        (see section 7.16.4) set to AutEeCancel.

  o  a failed authentication, then the failure should be reported to
     the Authenticatee and any further processing stopped.

  If the Authenticator receives an IOTP Message containing a Cancel
  block from a Consumer, then the Authenticatee may go to the
  CancelNetLocn specified on the Trading Role Element in the
  Organisation Component for the Authenticator contained in the Trading
  Protocol Options Block.

9.1.1.2 TPO & Authentication Request IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of:

  o a Trading Protocol Options Block (see section 8.1)

  o an Authentication Request Block (see section 8.4), and

  o an optional Signature Block (see section 8.16).

  Each of these are described below.

  TRADING PROTOCOL OPTIONS BLOCK

  The Trading Protocol Options Block (see section 8.1) must contain the
  following Trading Components:

  o  one Protocol Options Component (see Section 7.1) which defines the
     options which apply to the whole Authentication Document Exchange.

  o  one Organisation Component (see section 7.6) which describes the
     Authenticator. The Trading Role on the Organisation Component
     should indicate the role which the Authenticator is taking in the
     Trade, for example a Merchant or a Consumer.

  AUTHENTICATION REQUEST BLOCK

  The Authentication Request Block (see section 8.4) must contain the
  following Trading Components:

  o  one Authentication Request Component (see section 7.2), and




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RFC 2801                       IOTP/1.0                       April 2000


  SIGNATURE BLOCK (AUTHENTICATION REQUEST)

  If the Authentication Request is being digitally signed then a
  Signature Block must be included. It contains Digests of the
  following XML elements:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the TPO Block :

     -  the Protocol Options Component

     -  the Organisation Component

  o  the following components of the Authentication Request Block:

     -  the Authentication Request Component

     -  the Trading Role Information Request Component

9.1.1.3 Authentication Response IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of:

  o  an Authentication Response Block (see section 8.5), and

  o  an optional Signature Block (see section 8.16).

  Each of these are described below.

  AUTHENTICATION RESPONSE BLOCK

  The Authentication Response Block must contain the following Trading
  Component:

  o  one Authentication Response Component (see section 7.3)

  o  one Organisation Component for every Trading Role identified in
     the TradingRoleList attribute of the Trading Role Information
     Request Component contained in the Authentication Request Block.





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  SIGNATURE BLOCK (AUTHENTICATION RESPONSE)

  If the Algorithm element (see section 12. IANA Considerations) within
  the Authentication Request Component contained in the Authentication
  Request Block indicates that the Authentication Response should
  consist of a digital signature then a Signature Block must be
  included in the same IOTP message that contains an Authentication
  Response Block. The Signature Component contains Digest Elements for
  the following XML elements:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the Authentication Request Block:

     -  the Authentication Request Component

     -  the Trading Role Information Request Component

  o  the Organisation Components contained in the Authentication
     Response Block

  Note: It should not be assumed that all trading roles can support the
  signing of data. Particularly it should not be assumed that Consumers
  support the signing of data.

9.1.1.4 Authentication Status IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of:

  o  an Authentication Status Block (see section 8.5), and

  o  an optional Signature Block (see section 8.16).

  Each of these are described below.

  AUTHENTICATION STATUS BLOCK

  The Authentication Status Block (see section 8.6) must contain the
  following Trading Components:

  o  one Status Component (see section 7.16) with a ProcessState
     attribute set to CompletedOk.



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     SIGNATURE BLOCK (AUTHENTICATION STATUS)

     If the Authentication Status Block is being digitally signed then
     a Signature Block must be included that contains a Signature
     Component with Digest elements for the following XML elements:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the Authentication Status Block:

     -  the Status Component (see section 7.16).

  Note: If the Authentication Document Exchange is followed by an Offer
  Document Exchange (see section 9.1.2) then the Authentication Status
  Block and the Signature Block (Authentication Status) may be combined
  with either:

  o a TPO IOTP Message (see section 9.1.2.3), or

  o a TPO and Offer Response IOTP Message (see section 9.1.2.6)

9.1.2 Offer Document Exchange

  The Offer Document Exchange occurs in two basic forms:

  o  Brand Dependent Offer Exchange. Where the content of the offer,
     e.g., the order details, amount, delivery details, etc., are
     dependent on the payment brand and protocol selected by the
     consumer, and

  o  Brand Independent Offer Exchange. Where the content of the offer
     is not dependent on the payment brand and protocol selected.

     Each of these types of Offer Document Exchange may be preceded by
     an Authentication Document Exchange (see section 9.1.1).

9.1.2.1 Brand Dependent Offer Document Exchange

     In a Brand Dependent Offer Document Exchange the TPO Block and the
     Offer Response Block are sent separately by the Merchant to the
     Consumer, i.e.:





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  o  the Brand List Component is sent to the Consumer in a TPO Block,

  o  the Consumer selects a Payment Brand, Payment Protocol and
     optionally a Currency and amount from the Brand List Component

  o  the Consumer sends the selected brand, protocol and
     currency/amount back to the Merchant in a TPO Selection Block, and

  o  the Merchant uses the information received to define the content
     of and then send the Offer Response Block to the Consumer.









































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This is illustrated by the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
  Consumer
    |  Merchant
STEP |     |
1.          Consumer decides to trade and sends to the Merchant
            information (e.g., using HTML) that enables the Merchant
            to create an offer,

    C --> M Offer information - outside scope of IOTP

2.          Merchant decides which payment brand protocols,
            currencies and amounts apply, places then in a Brand List
            Component inside a TPO Block and sends to Consumer

    C <-- M TPO. IotpMsg: Trans Ref Block; TPO Block

3.          IOTP aware application started. Consumer selects the
            payment brand, payment protocol and currency/amount to
            use. Records selection in a Brand Selection Component and
            sends back to Merchant.

    C --> M TPO SELECTION. IotpMsg: Trans Ref Block; TPO Selection
            Block

4.          Merchant uses selected payment brand, payment protocol,
            currency/amount and the offer information to create an
            Offer Response Block containing details about the IOTP
            Transaction including price, etc. Optionally signs it and
            sends to the Consumer

    C <-- M OFFER RESPONSE. IotpMsg: Trans Ref Block; Signature Block
            (optional); Offer Response Block

5.          Consumer checks the Offer is OK, then combines components
            from the TPO Block, the TPO Selection Block and the Offer
            Response Block to create the next IOTP Message for the
            Transaction and sends it together with the Signature
            block if present to the required Trading Role

    CONTINUED ...

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

             Figure 19 Brand Dependent Offer Document Exchange





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  Note, a Consumer identifies a Brand Dependent Offer Document
  Exchange, by the absence of an Offer Response Block in the first IOTP
  Message.

  MESSAGE PROCESSING GUIDELINES

  On receiving a TPO IOTP Message (see below), the Consumer may either:

  o  generate and send a TPO Selection IOTP Message back to the
     Merchant, or

  o  indicate failure to continue with the IOTP Transaction by sending
     a Cancel Block back to the Merchant containing a Status Component
     with a StatusType of Offer, a ProcessState of Failed and the
     CompletionCode (see section 7.16.4) set to either: ConsCancelled
     or Unspecified.

  On receiving a TPO Selection IOTP Message (see below) the Merchant
  may either:

  o  generate and send an Offer Response IOTP Message back to the
     Consumer, or

  o  indicate failure to continue with the IOTP Transaction by sending
     a Cancel Block back to the Consumer containing a Status Component
     with a StatusType of Offer, a ProcessState of Failed and the
     CompletionCode (see section 7.16.4) set to either: MerchCancelled
     or Unspecified.

  On receiving an Offer Response IOTP Message (see below) the Consumer
  may either:

  o  generate and send the next IOTP Message in the IOTP transaction
     and send it to the required Trading Role. This is dependent on the
     IOTP Transaction, or

  o  indicate failure to continue with the IOTP Transaction by sending
     a Cancel Block back to the Merchant containing a Status Component
     with a StatusType of Offer, a ProcessState of Failed and the
     CompletionCode (see section 7.16.4) set to either: ConsCancelled
     or Unspecified.

  If the Merchant receives an IOTP Message containing a Cancel block,
  then the Consumer is likely to go to the CancelNetLocn specified on
  the Trading Role Element in the Organisation Component for the
  Merchant.





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  If the Consumer receives an IOTP Message containing a Cancel block,
  then the information contained in the IOTP Message should be reported
  to the Consumer but no further action taken.

9.1.2.2 Brand Independent Offer Document Exchange

  In a Brand Independent Offer Document Exchange the TPO Block and the
  Offer Response Block are sent together by the Merchant to the
  Consumer, i.e. there is one IOTP Message that contains both a TPO
  Block, and an Offer Response Block.

  The message flow is illustrated by the diagram below:

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
Consumer
    |  Merchant
STEP |     |
1.          Consumer decides to trade and sends to the Merchant
            information (e.g., using HTML) that enables the Merchant
            to create an offer,

    C --> M Offer information - outside scope of IOTP

2.          Merchant decides which payment brand protocols,
            currencies and amounts apply, places then in a Brand List
            Component inside a TPO Block, creates an Offer Response
            containing details about the IOTP Transaction including
            price, etc., optionally signs it  and sends to Consumer

    C <-- M TPO & OFFER RESPONSE. IotpMsg: Trans Ref Block; Signature
            Block; TPO Block; Offer Response Block

3.          IOTP aware application started. Consumer selects the
            payment brand, payment protocol and currency/amount to
            use. Records selection in a Brand Selection Component,
            checks offer is OK, combines the Brand Selection
            Component with information from the TPO Block and Offer
            Response Block to create the next IOTP Message for the
            Transaction and sends it together with the Signature
            Block if present to the required Trading Role.

    CONTINUED ...

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                Figure 20 Brand Independent Offer Exchange





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  Note that a Brand Independent Offer Document Exchange always occurs
  when only one payment brand, protocol and currency/amount is being
  offered to the Consumer by the Merchant. It is also likely to, but
  will not necessarily, occur when multiple brands are being offered,
  the Payment Handler is the same, and all brands use the same set of
  protocols.

  Note that the TPO Block and the Offer Response Block can be sent in
  separate IOTP messages (see Brand Dependent Offer Document Exchange)
  even if the Offer Response Block does not change. However this
  increases the number of messages in the transaction and is therefore
  likely to increase transaction response times.

  IOTP aware applications supporting the Consumer Trading Role must
  check for the existence of an Offer Response Block in the first IOTP
  Message to determine whether the Offer Document Exchange is brand
  dependent or not.

  MESSAGE PROCESSING GUIDELINES

  On receiving a TPO and Offer Response IOTP Message (see below), the
  Consumer may either:

  o  generate and send the next IOTP Message in the IOTP transaction
     and send it to the required Trading Role. This is dependent on the
     IOTP Transaction, or

  o  indicate failure to continue with the IOTP Transaction by sending
     a Cancel Block back to the Merchant containing a Status Component
     with a StatusType of Offer, a ProcessState of Failed and the
     CompletionCode (see section 7.16.1) set to either: ConsCancelled
     or Unspecified.

  If the Merchant receives an IOTP Message containing a Cancel block,
  then the Consumer is likely to go to the CancelNetLocn specified on
  the Trading Role Element in the Organisation Component for the
  Merchant.

9.1.2.3 TPO IOTP Message

  The TPO IOTP Message is only used with a Brand Dependent Offer
  Document Exchange. Apart from a Transaction Reference Block (see
  section 3.3), this message consists of just a Trading Protocol
  Options Block (see section 8.1) which is described below.







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  TPO (TRADING PROTOCOL OPTIONS) BLOCK

  The Trading Protocol Options Block (see section 8.1) must contain the
  following Trading Components:

  o  one Protocol Options Component which defines the options which
     apply to the whole IOTP Transaction. See Section 7.1.

  o  one Brand List Component (see section 7.7) for each Payment in the
     IOTP Transaction that contain one or more payment brands and
     protocols which may be selected for use in each payment

  o  Organisation Components (see section 7.6) with the following
     roles:

     -  Merchant who is making the offer

     -  Consumer who is carrying out the transaction

     -  the PaymentHandler(s) for the payment. The "ID" of the Payment
        Handler Organisation Component is contained within the PhOrgRef
        attribute of the Payment Component

  If the IOTP Transaction includes a Delivery then the TPO Block must
  also contain:

  o  Organisation Components with the following roles:

     -  DeliveryHandler who will be delivering the goods or services

     -  DelivTo i.e. the person or Organisation which is to take
        delivery

  AUTHENTICATION STATUS AND SIGNATURE BLOCKS

  If the Offer Document Exchange was preceded by an Authentication
  Document Exchange, then the TPO IOTP Message may also contain:

  o  an Authentication Status Block (see section 8.6), and

  o  an optional Signature Block (Authentication Status) Signature
     Block

  See section 9.1.1.4 Authentication Status IOTP Message for more
  details.






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9.1.2.4 TPO Selection IOTP Message

  The TPO Selection IOTP Message is only used with a Brand Dependent
  Offer Document Exchange. Apart from a Transaction Reference Block
  (see section 3.3), this message consists of just a TPO Selection
  Block (see section 8.1) which is described below.

  TPO SELECTION BLOCK

  The TPO Selection Block (see section 8.2) contains:

  o  one Brand Selection Component (see section 7.8) for use in a
     later Payment Exchange. It contains the results of the consumer
     selecting a Payment Brand, Payment Protocol and currency/amount
     from the list provided in the Brand List Component.

9.1.2.5 Offer Response IOTP Message

  The Offer Response IOTP Message is only used with a Brand Dependent
  Offer Document Exchange. Apart from a Transaction Reference Block
  (see section 3.3), this message consists of:

  o  an Offer Response Block (see section 8.1) and

  o  an optional Signature Block (see section 8.16).

  OFFER RESPONSE BLOCK

  The Offer Response Block (see section 8.3) contains the following
  components:

  o  one Status Component (see section 7.16) which indicates the status
     of the Offer Response. The ProcessState attribute should be set to
     CompletedOk

  o  one Order Component (see section 7.5) which contains details about
     the goods and services which are being purchased or the financial
     transaction which is taking place

  o  one or more Payment Component(s) (see section 7.9) for each
     payment which is to be made

  o  zero or one Delivery Components (see section 7.13) containing
     details of the delivery to be made if the IOTP Transaction
     includes a delivery

  o  zero or more Trading Role Data Components (see section 7.17) if
     required by the Merchant.



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  SIGNATURE BLOCK (OFFER RESPONSE)

  If the Authentication Status Block is being digitally signed then a
  Signature Block must be included that contains a Signature Component
  (see section 7.19) with Digest Elements for the following XML
  elements:

  If the Offer Response is being digitally signed then a Signature
  Block must be included that contains a Signature Component (see
  section 7.19) with Digest Elements for the following XML elements:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message that contains information that describes the IOTP Message
     and IOTP Transaction

  o  the Transaction Id Component (see section 3.3.1) which globally
     uniquely identifies the IOTP Transaction

  o  the following components of the TPO Block :

     -  the Protocol Options Component, and

     -  the Brand List Component

     -  all the Organisation Components present

  o  the following components of the Offer Response Block:

     -  the Order Component

     -  all the Payment Components present

     -  the Delivery Component if present

     -  any Trading Role Data Components present

9.1.2.6 TPO and Offer Response IOTP Message

  The TPO and Offer Response IOTP Message is only used with a Brand
  Independent Offer Document Exchange. Apart from a Transaction
  Reference Block (see section 3.3), this message consists of:

  o  a Trading Protocol Options Block (see section 8.1)

  o  an Offer Response Block (see section 8.1) and

  o  an optional Signature Block (see section 8.16).




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  TPO (TRADING PROTOCOL OPTIONS) BLOCK

  This is the same as the Trading Protocol Options Block described in
  TPO IOTP Message (see section 9.1.2.3).

  OFFER RESPONSE BLOCK

  This the same as the Offer Response Block in the Offer Response IOTP
  Message (see section 9.1.2.5).

  AUTHENTICATION STATUS

  If the Offer Document Exchange was preceded by an Authentication
  Document Exchange, then the TPO and Offer Response IOTP Message may
  also contain an Authentication Status Block (see section 8.6).

  SIGNATURE BLOCK

  This is the same as the Signature Block in the Offer Response IOTP
  Message (see section 9.1.2.5) with the addition that:

  o  if the Offer Document Exchange is Brand Dependent then the
     Signature Component in the Signature Block additionally contains a
     Digest Element for the Brand Selection Component contained in the
     TPO Selection Block

  o  if the Offer Document Exchange was preceded by an Authentication
     Document Exchange then the Signature Component in the Signature
     Block additionally contains a Digest Element for the
     Authentication Status Block.

9.1.3 Payment Document Exchange

  The Payment Document Exchange is a direct implementation of the last
  part of a Payment Trading Exchange (see section 2.2.2) after the
  Brand has been selected by the Consumer. A Payment Exchange consists
  of:

  o  the Consumer requesting that a payment starts by generating
     Payment Request IOTP Message using information from previous IOTP
     Messages in the Transaction and then sending it to the Payment
     Handler

  o  the Payment Handler and the Consumer then swapping Payment
     Exchange IOTP Messages encapsulating payment protocol messages
     until the payment is complete, and finally





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  o  the Payment Handler sending a Payment Response IOTP Message to the
     Consumer containing a receipt for the payment.

  The IOTP Messages which are involved are illustrated by the diagram
  below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
  Consumer
    |  Payment
    |  Handler
STEP |     |
1.          Consumer generates Pay Request Block encapsulating a
            payment protocol message if required and sends to Payment
            Handler with the Signature Block if present

    C --> P PAYMENT REQUEST. IotpMsg: Trans Ref Block; Signature
            Block (optional); Pay Request Block

2.          Payment Handler processes Pay Request Block, checks
            optional signature and starts exchanging payment protocol
            messages encapsulated in a Pay Exchange Block, with the
            Consumer

    C <-> P PAYMENT EXCHANGE. IotpMsg: Trans Ref Block; Pay Exchange
            Block

3.          Consumer and Payment Handler keep on exchanging Payment
            Exchange blocks until eventually payment protocol
            messages finish so Payment Handler creates a Pay Receipt
            Component inside a Pay Response Block, and an optional
            Signature Component inside a Signature Block, sends them
            to the Consumer and stops.

    C <-- P PAYMENT RESPONSE. IotpMsg: Trans Ref Block; Signature
            Block (optional); Pay Response Block

4.          Consumer checks Payment Response is OK. Optionally keeps
            information on IOTP Transaction for record keeping
            purposes and either stops or creates the next IOTP
            message for the Transaction and sends it together with
            the Signature Block, if present, to the required Trading
            Role

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                    Figure 21 Payment Document Exchange





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9.1.3.1 Message Processing Guidelines

  On receiving a Payment Request IOTP Message, the Payment Handler
  should check that they are authorised to carry out the Payment (see
  section 6 Digital Signatures). They may then either:

  o  generate and send a Payment Exchange IOTP Message back to the
     Consumer, if more payment protocol messages need to be exchanged,
     or

  o  generate and send a Payment Response IOTP Message if the exchange
     of payment protocol messages is complete, or

  o  indicate failure to continue with the Payment by sending a Cancel
     Block back to the Consumer containing a Status Component with a
     StatusType of Payment, a ProcessState of Failed and the
     CompletionCode (see section 7.16.4) set to either: BrandNotSupp,
     CurrNotSupp, PaymtCancelled, AuthError, InsuffFunds,
     InstBrandInvalid, InstNotValid, BadInstrument or Unspecified.

  On receiving a Payment Exchange IOTP Message, the Consumer may
  either:

  o  generate and send a Payment Exchange Message back to the Payment
     Handler or

  o  indicate failure to continue with the Payment by sending a Cancel
     Block back to the Payment Handler containing a Status Component
     with a StatusType of Payment, a ProcessState of Failed and the
     CompletionCode (see section 7.16.2) set to either: ConsCancelled
     or Unspecified.

  On receiving a Payment Exchange IOTP Message, the Payment Handler may
  either:

  o  generate and send a Payment Exchange IOTP Message back to the
     Consumer, if more payment protocol messages need to be exchanged,
     or

  o  generate and send a Payment Response IOTP Message if the exchange
     of payment protocol messages is complete, or

  o  indicate failure to continue with the Payment by sending a Cancel
     Block back to the Consumer containing a Status Component with a
     StatusType of Payment, a ProcessState of Failed and the
     CompletionCode (see section 7.16.2) set to either: PaymtCancelled
     or Unspecified.




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  On receiving a Payment Response IOTP Message, the Consumer may
     either:

  o  generate and send the next IOTP Message in the IOTP transaction
     and send it to the required Trading Role. This is dependent on the
     IOTP Transaction,

  o  stop, since the IOTP Transaction has ended, or

  o  indicate failure to continue with the IOTP Transaction by sending
     a Cancel Block back to the Merchant containing a Status Component
     with a StatusType of Payment, a ProcessState of Failed and the
     CompletionCode (see section 7.16.1) set to either: ConsCancelled
     or Unspecified.

  If the Consumer receives an IOTP Message containing a Cancel block,
  then the information contained in the IOTP Message should be reported
  to the Consumer but no further action taken.

  If the Payment Handler receives an IOTP Message containing a Cancel
  block, then the Consumer is likely to go to the CancelNetLocn
  specified on the Trading Role Element in the Organisation Component
  for the Payment Handler from which any further action may take place.

  If the Merchant receives an IOTP Message containing a Cancel block,
  then the Consumer should have completed the payment but not
  continuing with the transaction for some reason. In this case the
  Consumer is likely to go to the CancelNetLocn specified on the
  Trading Role Element in the Organisation Component for the Merchant
  from which any further action may take place.

9.1.3.2 Payment Request IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of:

  o  a Payment Request Block, and

  o  an optional Signature Block

  PAYMENT REQUEST BLOCK

  The Payment Request Block (see section 8.7) contains:

  o  the following components copied from the Offer Response Block from
     the preceding Offer Document Exchange:

     -  the Status Component



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     -  the Payment Component for the payment which is being carried
        out

  o  the following components from the TPO Block:

     -  the Organisation Components with the roles of Merchant and for
        the PaymentHandler that is being sent the Payment Request Block

     -  the Brand List Component for the payment, i.e. the Brand List
        referred to by the BrandListRef attribute on the Payment
        Component

  o  one Brand Selection Component for the Brand List, i.e. the Brand
     Selection Component where BrandListRef attribute points to the
     Brand List. This component can be either:

     -  copied from the TPO Selection Block if the payment was preceded
        by a Brand Dependent Offer Document Exchange (see section
        9.1.2.1), or

     -  created by the Consumer, containing the payment brand, payment
        protocol and currency/amount selected from the Brand List, if
        the payment was preceded by a Brand Independent Offer Document
        Exchange (see section 9.1.2.2)

  o  an optional Payment Scheme Component (see section 7.10) if
     required by the payment method used (see the Payment Method
     supplement to determine if this is needed).

  o  zero or more Trading Role Data Components (see section 7.17).

  Note that:

  o  if there is more than one Payment Components in an Offer Response
     Block, then the second payment is the one within the Offer
     Response Block that contains a StartAfter attribute (see section
     7.9) that identifies the Payment Component for the first payment

  o  the Payment Handler to include is identified by the Brand
     Selection Component (see section 7.8) for the payment. Also see
     section 6.3.1 Check Request Block sent Correct Organisation for an
     explanation on how Payment Handlers are identified

  o  the Brand List Component to include is the one identified by the
     BrandListRef attribute of the Payment Component for the identified
     payment





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  o  the Brand Selection Component to include from the Offer Response
     Block is the one that contains an BrandListRef attribute (see
     section 3.5) which identifies the Brand List Component for the
     second payment.

  SIGNATURE BLOCK (PAYMENT REQUEST)

  If the either the preceding Offer Document Exchange included an Offer
  Response Signature (see section 9.1.2.5 Offer Response IOTP Message),
  or a preceding Payment Exchange included a Payment Response Signature

  (see section 9.1.3.4 Payment Response IOTP Message) then they should
  both be copied to the Signature Block in the Payment Request IOTP
  Message.

9.1.3.3 Payment Exchange IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of just a Payment Exchange Block.

  PAYMENT EXCHANGE BLOCK

  The Payment Exchange Block (see section 8.8) contains:

  o  one Payment Scheme Component (see section 7.10) which contains
     payment method specific data. See the Payment Method supplement
     for the payment method being used to determine what this should
     contain.

9.1.3.4 Payment Response IOTP Message

  Apart from a Transaction Reference Block (see section 3.3), this
  message consists of:

  o  a Payment Response Block, and

  o  an optional Signature Block

  PAYMENT RESPONSE BLOCK

  The Payment Response Block (see section 8.9) contains:

  o  one Payment Receipt Component (see section 7.11) which contains
     scheme specific data which can be used to verify the payment
     occurred






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  o  one Payment Scheme Component (see section 7.10) if required which
     contains payment method specific data. See the Payment Method
     supplement for the payment method being used to determine what
     this should contain

  o  an optional Payment Note Component (see section 7.12)

  o  zero or more Trading Role Data Components (see section 7.17).

  SIGNATURE BLOCK (PAYMENT RESPONSE)

  If a signed Payment Receipt is being provided, indicated by the
  SignedPayReceipt attribute of the Payment Component being set to
  True, then the Signature Block should contain a Signature Component
  which contains Digest Elements for the following:

  o  the Transaction Reference Block (see section 3.3) for the IOTP
     Message which contains the first usage of the Payment Response
     Block,

  o  the Transaction Id Component (see section 3.3.1) within the
     Transaction Reference Block that globally uniquely identifies the
     IOTP Transaction,

  o  the Payment Receipt Component from the Payment Response Block,

  o  the Payment Note Component from the Payment Response Block,

  o  the other Components referenced by the PayReceiptNameRefs
     attribute (if present) of the Payment Receipt Component,

  o  the Status Component from the Payment Response Block,

  o  any Trading Role Data Components in the Payment Response Block,
     and

  o  all the Signature Components contained in the Payment Request
     Block if present.

9.1.4 Delivery Document Exchange

  The Delivery Document Exchange is a direct implementation of a
  Delivery Trading Exchange (see section 2.2.3). It consists of:

  o  the Consumer requesting a Delivery by generating Delivery Request
     IOTP Message using information from previous IOTP Messages in the
     Transaction and then sending it to the Delivery Handler




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  o  the Delivery Handler sending a Delivery Response IOTP Message to
     the Consumer containing details about the Handler's response to
     the request together with an optional signature.

  The message flow is illustrated by the diagram below.

*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
Consumer
    |  Delivery
    |  Handler
STEP |     |
1.          Consumer generates Delivery Request Block and sends it to
            the Delivery Handler with the Signature Block if present

    C --> D DELIVERY REQUEST. IotpMsg: Trans Ref Block; Signature
            Block; Delivery Request Block

2.          Delivery Handler checks the Status and Order Components
            in the Delivery Request and the optional Signatures,
            creates a Delivery Response Block, sends to the Consumer
            and stops.

    C <-- D DELIVERY RESPONSE. IotpMsg: Trans Ref Block; Signature
            Block; Delivery Response Block

3.           Consumer checks Delivery Response Block and optional
            Signature Block are OK. Optionally keeps information on
            IOTP Transaction for record keeping purposes and stops.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                   Figure 22 Delivery Document Exchange

9.1.4.1 Message Processing Guidelines

  On receiving a Delivery Request IOTP Message, the Delivery Handler
  should check that they are authorised to carry out the Delivery (see
  section 6 Digital Signatures). They may then either:

  o  generate and send a Delivery Response IOTP Message to the
     Consumer, or

  o  indicate failure to continue with the Delivery by sending a Cancel
     Block back to the Consumer containing a Status Component with a
     StatusType of Delivery, a ProcessState of Failed and the
     CompletionCode (see section 7.16.4) set to either: DelivCanceled,
     or Unspecified.




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  On receiving a Delivery Response IOTP Message, the Consumer should
  just stop since the IOTP Transaction is complete.

  If the Consumer receives an IOTP Message containing a Cancel block,
  then the information contained in the IOTP Message should be reported
  to the Consumer but no further action taken.

9.1.4.2 Delivery Request IOTP Message

  The Delivery Request IOTP Message consists of:

  o  a Delivery Request Block, and

  o  an optional Signature Block

  DELIVERY REQUEST BLOCK

  The Delivery Request Block (see section 8.10) contains:

  o  the following components copied from the Offer Response Block:

     -  the Status Component (see section 7.16)

     -  the Order Component (see section 7.5)

     -  the Organisation Component (see section 7.6) with the roles of:
        Merchant, DeliveryHandler and DeliverTo

     -  the Delivery Component (see section 7.13)

  o  the following Component from the Payment Response Block:

     -  the Status Component (see section 7.16).

  o  zero or more Trading Role Data Components (see section 7.17).

  SIGNATURE BLOCK (DELIVERY REQUEST)

  If the preceding Offer Document Exchange included an Offer Response
  Signature or the Payment Document Exchange included a Payment
  Response Signature, then they should both be copied to the Signature
  Block.

9.1.4.3 Delivery Response IOTP Message

  The Delivery Response IOTP Message contains a Delivery Response Block
  and an optional Signature Block.




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  DELIVERY RESPONSE BLOCK

  The Delivery Response Block contains:

  o  one Delivery Note Component (see section 7.15) which contains
     delivery instructions about the delivery of goods or services

     in3 SIGNATURE BLOCK (DELIVERY RESPONSE)

     The Signature Block should contain one Signature Component that
     contains Digest elements that refer to

  o  the Transaction Id Component (see section 3.3.1) of the IOTP
     message that contains the Delivery  Response Signature

  o  the Transaction Reference Block (see section 3.3) of the IOTP
     Message that contains the Delivery  Response Signature

  o  the Consumer Delivery Data component contained in the Delivery
     Request Block (if any)

  o  the Signature Components contained in the Delivery Request Block
     (if any)

  o  the Status Component

  o  the Delivery Note Component

9.1.5 Payment and Delivery Document Exchange

  The Payment and Delivery Document Exchange is a combination of the
  last part of the Payment Trading Exchange (see section 2.2.2) and a
  Delivery Trading Exchange (see section 2.2.3). It consists of:

  o  the Consumer requesting that a payment starts by generating
     Payment Request IOTP Message using information from previous IOTP
     Messages in the Transaction and then sending it to the Payment
     Handler

  o  the Payment Handler and the Consumer then swapping Payment
     Exchange IOTP Messages encapsulating payment protocol messages
     until the payment is complete, and finally

  o  the Payment Handler sending to the Consumer in one IOTP Message:

     -  a Payment Response Block containing a receipt for the payment,
        and




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     -  a Delivery Response Block containing details of the goods or
        services to be delivered

  The IOTP Messages which are involved are illustrated by the diagram
  below.














































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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
Consumer
    |  Payment
    |  Handler
STEP |     |
1.          Consumer generates Pay Request Block encapsulating a
            payment protocol message if required and sends to Payment
            Handler with the Signature Block if present

    C --> P PAYMENT REQUEST. IotpMsg: Trans Ref Block; Signature
            Block; Pay Request Block

2.          Payment Handler processes Pay Request Block, checks
            optional signature and starts exchanging payment protocol
            messages encapsulated in a Pay Exchange Block, with the
            Consumer

    C <-> P PAYMENT EXCHANGE. IotpMsg: Trans Ref Block; Pay Exchange
            Block

3.          Consumer and Payment Handler keep on exchanging Payment
            Exchange blocks until eventually payment protocol
            messages finish so Payment Handler creates a Pay Receipt
            Component inside a Pay Response Block, and an optional
            Signature Component inside a Signature Block, then uses
            information from the Offer Response Bock to create a
            Delivery Response Block and sends both to the Consumer
            and stops.

    C <-- P PAYMENT RESPONSE & DELIVERY RESPONSE. IotpMsg: Trans Ref
            Block; Signature Block; Pay Response Block; Delivery
            Response Block

4.          Consumer checks Payment Response and Delivery Response
            Blocks are OK. Optionally keeps information on IOTP
            Transaction for record keeping purposes and either stops
            or creates the next IOTP message for the Transaction and
            sends it together with the Signature Block, if present,
            to the required Trading Role

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

             Figure 23 Payment and Delivery Document Exchange








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  The Delivery Response Block and the Payment Response Block may be
  combined into the same IOTP Message only if the Payment Handler has
  the information available so that she can send the Delivery Response
  Block.  This is likely to, but will not necessarily, occur when the
  Merchant, the Payment Handler and the Delivery Handler Roles are
  combined.

  The DelivAndPayResp attribute of the Delivery Component (see section
  7.13) contained within the Offer Response Block (see section 8.3) is
  set to True if the Delivery Response Block and the Payment Response
  Block are combined into the same IOTP Message and is set to False if
  the Delivery Response Block and the Payment Response Block are sent
  in separate IOTP Messages.

9.1.5.1 Message Processing Guidelines

  On receiving a Payment Request IOTP Message or a Payment Exchange
  IOTP Message, the Payment Handler should carry out the same actions
  as for a Payment Document Exchange (see section 9.1.3.1).

  On receiving a Payment Exchange IOTP Message, the Consumer should
  also carry out the same actions as for a Payment Document Exchange
  (see section 9.1.3.1).

  On receiving a Payment Response and Delivery Response IOTP Message
  then the IOTP Transaction is complete and should take no further
  action.

  If the Consumer receives an IOTP Message containing a Cancel block,
  then the information contained in the IOTP Message should be reported
  to the Consumer but no further action taken.

  If the Payment Handler receives an IOTP Message containing a Cancel
  block, then the Consumer is likely to go to the CancelNetLocn
  specified on the Trading Role Element in the Organisation Component
  for the Payment Handler from which any further action may take place.

  If the Merchant receives an IOTP Message containing a Cancel block,
  then the Consumer should have completed the payment but not
  continuing with the transaction for some reason. In this case the
  Consumer is likely to go to the CancelNetLocn specified on the
  Trading Role Element in the Organisation Component for the Merchant
  from which any further action may take place.

9.1.5.2 Payment Request IOTP Message

  The content of this message is the same as for a Payment Request IOTP
  Message in a Payment Document Exchange (see section 9.1.3.2).



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9.1.5.3 Payment Exchange IOTP Message

  The content of this message is the same as for a Payment Exchange
  IOTP Message in a Payment Document Exchange (see section 9.1.3.3).

9.1.5.4 Payment Response and Delivery Response IOTP Message

  The content of this message consists of:

  o  a Payment Response Block,

  o  an optional Signature Block (Payment Response), and

  o  a Delivery Response Block.

  PAYMENT RESPONSE BLOCK

  The content of this block is the same as the Payment Response Block
  in the Payment Response IOTP Message associated with a Payment
  Document Exchange (see section 9.1.3.4).

  SIGNATURE BLOCK (PAYMENT RESPONSE)

  The content of this block is the same as the Signature Block (Payment
  Response) in the Payment Response IOTP Message associated with a
  Payment Document Exchange (see section 9.1.3.4).

  DELIVERY RESPONSE BLOCK

  The content of this block is the same as the Delivery Response Block
  in the Delivery Response IOTP Message associated with a Delivery
  Document Exchange (see section 9.1.4.3).

9.1.6 Baseline Authentication IOTP Transaction

  A Baseline Authentication IOTP Transaction may occur at any time
  between any of the Trading Roles involved in IOTP Transactions. This
  means it could occur:

  o  before another IOTP Transaction

  o  at the same time as another IOTP Transaction

  o  independently of any other IOTP Transaction.

  The Baseline Authentication IOTP Transaction consists of just an
  Authentication Document Exchange (see section 9.1.1) as illustrated
  by the diagram below.



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  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -------------------------------------------------------
                                                               v
                                                      ----------------
                                                     | AUTHENTICATION |
                                                      ----------------
                                                                |
                                                                |
                                                                |
                                                                |
                 -------------------     -----------------      |
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
                |       OFFER       |   |      OFFER      |     |
                 -------------------     -----------------      |
                                                                |
                                                                |
                                                                |
                                                                |
                                                                |
                     ---------           --------------         |
                    | PAYMENT |         | PAYMENT WITH |        |
                    | (first) |         |   DELIVERY   |        |
                     ---------           --------------         |
                                                                |
                                                                |
                                                                |
        ----------        ---------                             |
       | DELIVERY |      | PAYMENT |                            |
       |          |      | {second)|                            |
        ----------        ---------                             |
                                                                v
                                                              STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

              Figure 24 Baseline Authentication IOTP Transaction

  Example uses of the Baseline Authentication IOTP Transaction include:

  o  when the Baseline Authentication IOTP Transaction takes place as
     an early part of a session where strong continuity exists. For
     example, a Financial Institution could:

     -  set up a secure channel (e.g., using [SSL/TLS]) with a customer

     -  authenticate the customer using the Baseline Authentication
        IOTP Transaction, and then



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     -  provide the customer with access to account information and
        other services with the confidence that they are communicating
        with a bona fide customer.

  o  as a means of providing a Merchant role with Organisation
     Components that contain information about Consumer and DelivTo
     Trading Roles

  o  so that a Consumer may authenticate a Payment Handler before
     starting a payment.

9.1.7 Baseline Deposit IOTP Transaction

  The Baseline Deposit IOTP Transaction supports the deposit of
  electronic cash with a Financial Institution.

  Note: The Financial Institution has, in IOTP terminology, a role of
  merchant in that a service (i.e. a deposit of electronic cash) is
  being offered in return for a fee, for example bank charges of some
  kind. The term "Financial Institution" is used in the diagrams and in
  the text for clarity.

  The Baseline Deposit IOTP Transaction consists of the following
  Document Exchanges:

  o  an optional Authentication Document Exchange (see section 9.1.1)

  o  an Offer Document Exchange (see section 9.1.2), and

  o  a Payment Document Exchange (see section 9.1.3).

  The way in which these Document Exchanges may be combined together is
  illustrated by the diagram below.


















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  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -----------------------------------------------------
     |                                                       v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |
                      |                     |              |
                      |      -------------- | -------------
                      v      v              v      v
                 -------------------     -----------------
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |
                |       OFFER       |   |      OFFER      |
                 -------------------     -----------------
                       |                        |
                       |                        |
                       |                        |
                       |     -------------------
                       v    v
                     ---------           --------------
                    | PAYMENT |         | PAYMENT WITH |
                    | (first) |         |   DELIVERY   |
                     ---------           --------------
                         |
                          ----------------
                                          |
        ----------        ---------       |
       | DELIVERY |      | PAYMENT |      |
       |          |      | {second)|      |
        ----------        ---------       |
                                          |
                                           -----------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                  Figure 25 Baseline Deposit IOTP Transaction

  See section 9.1.12 "Valid Combinations of Document Exchanges" to
  determine which combination of document exchanges apply to a
  particular instance of an IOTP Transaction

  Note that:

  o  a Merchant (Financial Institution) may be able to accept a deposit
     in several different types of electronic cash although, since the
     Consumer role that is depositing the electronic cash usually knows
     what type of cash they want to deposit, it is usually constrained



Burdett                      Informational                    [Page 219]

RFC 2801                       IOTP/1.0                       April 2000


     in practice to only one type. However, there may be several
     different protocols which may be used for the same "brand" of
     electronic cash. In this case a Brand Dependent Offer may be
     appropriate to negotiate the protocol to be used.

  o  the Merchant (Financial Institution) may use the results of the
     authentication to identify not only the consumer but also the
     account to which the payment is to be deposited. If no single
     account can be identified, then it must be obtained by other
     means. For example:

     -  the consumer could specify the account number prior to the
        Baseline Deposit IOTP Transaction starting, or

     -  the consumer could have been identified earlier, for example
        using a Baseline Authentication IOTP Transaction, and an
        account selected from a list provided by the Financial
        Institution.

  o  The Baseline Deposit IOTP Transaction without an Authentication
     Document Exchange might be used:

     -  if a previous IOTP transaction, for example a Baseline
        Withdrawal or a Baseline Authentication, authenticated the
        consumer, and a secure channel has been maintained, therefore
        the authenticity of the consumer is known

     -  if authentication is achieved as part of a proprietary payment
        protocol and is therefore included in the Payment Document
        Exchange

     -  if authentication of the consumer has been achieved by some
        other means outside of the scope of IOTP, for example, by using
        a pass phrase, or a proprietary banking software solution.

9.1.8 Baseline Purchase IOTP Transaction

  The Baseline Purchase IOTP Transaction supports the purchase of goods
  or services using any payment method. It consists of the following
  Document Exchanges:

  o  an optional Authentication Document Exchange (see section 9.1.1)

  o  an Offer Document Exchange (see section 9.1.2)

  o  either:

     -  a Payment Document Exchange (see section 9.1.3) followed by



Burdett                      Informational                    [Page 220]

RFC 2801                       IOTP/1.0                       April 2000


     -  a Delivery Document Exchange (see section 9.1.4)

  o  a Payment Document Exchange only, or

  o  a combined Payment and Delivery Document Exchange (see section
     9.1.5).

  The ways in which these Document Exchanges are combined is
  illustrated by the diagram below.

  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -----------------------------------------------------
     |                                                       v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |    |
                      |                     |              |    |
                      |      -------------- | -------------     |
                      v      v              v      v            |
                 -------------------     -----------------      |
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
                |       OFFER       |   |      OFFER      |     |
                 -------------------     -----------------      |
                       |    |                   |   |           |
                       |     ---------------    |   |           |
                       |                    |   |   |           |
                       |     -------------- | --    |           |
                       v    v               v       v           |
                     ---------           --------------         |
                    | PAYMENT |         | PAYMENT WITH |        |
                    | (first) |         |   DELIVERY   |        |
                     ---------           --------------         |
                         |                      |               |
             -----------------------------      |               |
             v                            |     |               |
        ----------        ---------       |     |               |
       | DELIVERY |      | PAYMENT |      |     |               |
       |          |      | {second)|      |     |               |
        ----------        ---------       |     |               |
             |                            |     |               v
              ----------------------------------------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                 Figure 26 Baseline Purchase IOTP Transaction




Burdett                      Informational                    [Page 221]

RFC 2801                       IOTP/1.0                       April 2000


  See section 9.1.12 "Valid Combinations of Document Exchanges" to
  determine which combination of document exchanges apply to a
  particular instance of an IOTP Transaction.

9.1.9 Baseline Refund IOTP Transaction

  In business terms the refund process typically consists of:

  o  a request for a refund being made by the Consumer to the Merchant,
     typically supported by evidence to demonstrate:

     -  the original trade took place, for example by providing a
        receipt for the original transaction

     -  using some type of authentication, that the consumer requesting
        the refund is the consumer, or a representative of the
        consumer, who carried out the original trade

     -  the reason why the merchant should make the refund

  o  the merchant agreeing (or not) to the refund. This may involve
     some negotiation between the Consumer and the Merchant, and, if
     the merchant agrees,

  o  a refund payment by the Merchant to the Consumer.

  The Baseline Refund IOTP Transaction supports a subset of the above,
  specifically it supports:

  o  stand alone authentication of the Consumer using a separate
     Baseline Authentication IOTP Transaction (see section 9.1.6)

  o  a refund payment by the Merchant to the Consumer using the
     following two Trading Exchanges:

     -  an optional Authentication Document Exchange (see section
        9.1.1)

     -  an Offer Document Exchange (see section 9.1.2), and

     -  a Payment Document Exchange (see section 9.1.3).

  The ways in which these Document Exchanges are combined is
  illustrated by the diagram below.







Burdett                      Informational                    [Page 222]

RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -----------------------------------------------------
     |                                                       v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |
                      |                     |              |
                      |      -------------- | -------------
                      v      v              v      v
                 -------------------     -----------------
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |
                |       OFFER       |   |      OFFER      |
                 -------------------     -----------------
                       |                        |
                       |                        |
                       |                        |
                       |     -------------------
                       v    v
                     ---------           --------------
                    | PAYMENT |         | PAYMENT WITH |
                    | (first) |         |   DELIVERY   |
                     ---------           --------------
                         |
                          ----------------
                                          |
        ----------        ---------       |
       | DELIVERY |      | PAYMENT |      |
       |          |      | {second)|      |
        ----------        ---------       |
                                          |
                                           -----------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                  Figure 27 Baseline Refund IOTP Transaction

  A Baseline Refund IOTP Transaction without an Authentication Document
  Exchange might be used:

  o  when authentication of the consumer has been achieved by some
     other means, for example, the consumer has entered some previously
     supplied code in order to identify herself and the refund to which
     the code applies. The code could be supplied, for example on a web
     page or by e-mail.





Burdett                      Informational                    [Page 223]

RFC 2801                       IOTP/1.0                       April 2000


  o  when a previous IOTP transaction, for example a Baseline
     Authentication, authenticated the consumer, and a secure channel
     has been maintained, therefore the authenticity of the consumer is
     known and therefore the previously agreed refund can be
     identified.

  o  when the authentication of the consumer is carried out by the
     Payment Handler using a payment scheme authentication algorithm.

9.1.10 Baseline Withdrawal IOTP Transaction

  The Baseline Withdrawal IOTP Transaction supports the withdrawal of
  electronic cash from a Financial Institution.

  Note: The Financial Institution has, in IOTP terminology, a role of
  merchant in that a service (i.e. a withdrawal of electronic cash) is
  being offered in return for a fee, for example bank charges of some
  kind. The term "Financial Institution" is used in the diagrams and in
  the text for clarity.

  The Baseline Withdrawal IOTP Transaction consists of the following
  Document Exchanges:

  o  an optional Authentication Document Exchange (see section 9.1.1)

  o  an Offer Document Exchange (see section 9.1.2), and

  o  a Payment Document Exchange (see section 9.1.3).

  The way in which these Document Exchanges may be combined together is
  illustrated by the diagram below.




















Burdett                      Informational                    [Page 224]

RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -----------------------------------------------------
     |                                                       v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |
                      |                     |              |
                      |      -------------- | -------------
                      v      v              v      v
                 -------------------     -----------------
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |
                |       OFFER       |   |      OFFER      |
                 -------------------     -----------------
                       |                        |
                       |                        |
                       |                        |
                       |     -------------------
                       v    v
                     ---------           --------------
                    | PAYMENT |         | PAYMENT WITH |
                    | (first) |         |   DELIVERY   |
                     ---------           --------------
                         |
                          ----------------
                                          |
        ----------        ---------       |
       | DELIVERY |      | PAYMENT |      |
       |          |      | {second)|      |
        ----------        ---------       |
                                          |
                                           -----------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                Figure 28 Baseline Withdrawal IOTP Transaction

  Note that:

  o  a Merchant (Financial Institution) may be able to offer withdrawal
     of several different types of electronic cash. In practice usually
     only one form of electronic cash may be offered. However, there
     may be several different protocols which may be used for the same
     "brand" of electronic cash.






Burdett                      Informational                    [Page 225]

RFC 2801                       IOTP/1.0                       April 2000


  o  the Merchant (Financial Institution) may use the results of the
     authentication to identify not only the consumer but also the
     account from which the withdrawal is to be made. If no single
     account can be identified, then it must be obtained by other
     means. For example:

     -  the consumer could specify the account number prior to the
        Baseline Withdrawal IOTP Transaction starting, or

     -  the consumer could have been identified earlier, for example
        using a Baseline Authentication IOTP Transaction, and an
        account selected from a list provided by the Financial
        Institution.

  o  a Baseline Withdrawal without an authentication might be used:

     -  if a previous IOTP transaction, for example a Baseline Deposit
        or a Baseline Authentication, authenticated the consumer, and a
        secure channel has been maintained, therefore the authenticity
        of the consumer is known

     -  if authentication is achieved as part of a proprietary payment
        protocol and is therefore included in the Payment Document
        Exchange

     -  if authentication of the consumer has been achieved by some
        other means, for example, by using a pass phrase, or a
        proprietary banking software solution.

9.1.11 Baseline Value Exchange IOTP Transaction

  The Baseline Value Exchange Transaction uses Payment Document
  Exchanges to support the exchange of value in one currency obtained
  using one payment method with value in the same or another currency
  using the same or another payment method. Examples of its use
  include:

  o  electronic cash advance on a credit card. For example the first
     payment could be a "dollar SET Payment" using a credit card with
     the second payment being a download of Visa Cash e-cash in
     dollars.

  o  foreign exchange using the same payment method. For example the
     payment could be an upload of Mondex value in British Pounds and
     the second a download of Mondex value in Euros






Burdett                      Informational                    [Page 226]

RFC 2801                       IOTP/1.0                       April 2000


  o  foreign exchange using different payment methods. For example the
     first payment could be a SET payment in Canadian Dollars followed
     a download of GeldKarte in Deutchmarks.

  The Baseline Value Exchange uses the following Document Exchanges:

  o  an optional Authentication Document Exchange (see section 9.1.1)

  o  an Offer Document Exchange (see section 9.1.2), which provides
     details of what values and currencies will be exchanged, and

  o  two Payment Document Exchanges (see section 9.1.3) which carry out
     the two payments involved.

  The way in which these Document Exchanges may be combined together is
  illustrated by the diagram below.



































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RFC 2801                       IOTP/1.0                       April 2000


  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START -----------------------------------------------------
     |                                                         v
     |                                                ----------------
     |                                               | AUTHENTICATION |
     |                                                ----------------
      --------------------------------------               |
                      |                     |              |
                      |      -------------- | -------------
                      v      v              v      v
                 -------------------     -----------------
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |
                |       OFFER       |   |      OFFER      |
                 -------------------     -----------------
                       |                        |
                       |                        |
                       |                        |
                       |     -------------------
                       v    v
                     ---------           --------------
                    | PAYMENT |         | PAYMENT WITH |
                    | (first) |         |   DELIVERY   |
                     ---------           --------------
                         |
                          ----
                              v
        ----------        ---------
       | DELIVERY |      | PAYMENT |
       |          |      | {second)|
        ----------        ---------
                              |
                               -----------------------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

              Figure 29 Baseline Value Exchange IOTP Transaction














Burdett                      Informational                    [Page 228]

RFC 2801                       IOTP/1.0                       April 2000


  The Baseline Value Exchange IOTP Transaction occurs in two basic
  forms:

  o  Brand Dependent Value Exchange. Where the content of the offer,
     for example the rate at which one form of value is exchanged for
     another, is dependent on the payment brands and protocols selected
     by the consumer, and

  o  Brand Independent Value Exchange. Where the content of the offer
     is not dependent on the payment brands and protocols selected.

  Note: In the above the role is a Merchant even though the
  Organisation carrying out the Value Exchange may be a Bank or some
  other Financial Institution. This is because the Bank is acting as a
  merchant in that they are making an offer which the Consumer can
  either accept or decline.

  The TPO Block and Offer Response Block may only be combined into the
  same IOTP Message if the content of the Offer Response Block does not
  change as a result of selecting the payment brands and payment
  protocols to be used in the Value Exchange.

  BASELINE VALUE EXCHANGE SIGNATURES

  The use of signatures to ensure the integrity of a Baseline Value
  Exchange is illustrated by the diagram below.

























Burdett                      Informational                    [Page 229]

RFC 2801                       IOTP/1.0                       April 2000


*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

Signature generated                  IotpMsg (TPO)
by Merchant ensures                  - Trans Ref Block
integrity of the Offer -------->  -  - Signature Block
                                |   - TPO Block              MERCHANT
                                |   - Offer Response Block
                                |
Signature generated by           |
the Payment Handler of           |   IotpMsg (Pay Resp 1)
the first payment binds          |   - Trans Ref Block         PAYMENT
Pay Receipt for the first ----->  -> - Signature Block -----   HANDLER
payment to the Offer                 - Pay Response Block 1 |    1
                                                           |
Signature generated by                                      |
the Payment Handler of           IotpMsg (Pay Resp 2)       |  PAYMENT
the second payment binds           - Trans Ref Block        |  HANDLER
the second payment to the ----->   - Signature Block <------     2
first payment and therefore        - Pay Response Block 2
to the Offer

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

             Figure 30 Baseline Value Exchange Signatures

9.1.12 Valid Combinations of Document Exchanges

  The following diagram illustrates the data conditions in the various
  IOTP messages which can be used by a Consumer Trading Role to
  determine whether the combination of Document Exchanges are valid.

  *+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  START
    |
    v
  Auth Request Block in  =TRUE
   first IOTP Message ? ---------------------------------------
     | = FALSE                                                 |
     v                                                         v
  Offer Response Block in                             ----------------
    first IOTP Message ?                             | AUTHENTICATION |
     |=TRUE         |=FALSE                           ----------------
     |              |                                        |
     |              |                                        v






Burdett                      Informational                    [Page 230]

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     |                ----------------------       TPO & Offer Response
      -------------                         |   Blocks in last IOTP Msg
                   |                        |     |=TRUE        |=FALSE
                   |                        |     |             v
                   |          ------------- | ----    TPO Block only if
                   |         |              |         last IOTP Message
                   |         |              |         of Authentication
                   |         |              |          |=TRUE   |=FALSE
                   v         v              v          v        |
                 -------------------     -----------------      |
                | BRAND INDEPENDENT |   | BRAND DEPENDENT |     |
                |       OFFER       |   |      OFFER      |     |
                 -------------------     -----------------      |
                         |                   |                  |
                         v                   v                  |
                      Offer Response Block contains             |
                            Delivery Component ?                |
                           |=FALSE        |=TRUE                |
                        ---               v                     |
                       |        Value of DelivAndPayResp        |
                       |    attribute of Delivery Component ?   |
                       |    |=FALSE         |=TRUE              |
                       |    |               |                   |
                       v    v               v                   |
                     ---------           --------------         |
                    | PAYMENT |         | PAYMENT WITH |        |
                    | (first) |         |   DELIVERY   |        |
                     ---------           --------------         |
                         |                      |               |
                         v                      |               |
           Offer and Response Block contains     -------------->|
                 Delivery Component ?                           |
                 |=TRUE           |=FALSE                       |
                 |                v                             |
                 |         Two Payment Components               |
                 |      present in Offer Response Block?        |
                 |           |=TRUE             |=FALSE         |
                 v           v                  |               |
        ----------        ---------             |               |
       | DELIVERY |      | PAYMENT |            |               |
       |          |      | {second)|            |               |
        ----------        ---------             |               |
             |                |                 |               v
              ----------------------------------------------> STOP

  *-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

              Figure 31 Valid Combinations of Document Exchanges



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  1) If first IOTP Message of an IOTP Transaction contains an
     Authentication Request then:

     a) IOTP Transaction includes an Authentication Document Exchange
        (see section 9.1.1). (Note 1)

     b) If the last IOTP Message of the Authentication Document
        Exchange includes a TPO Block and an Offer Response Block then:

        i) IOTP Transaction includes a Brand Independent Offer Document
           Exchange (see section 9.1.2.2). (Note 2)

     c) Otherwise, if the last IOTP Message of the Authentication
        Exchange includes a TPO Block but NO Offer Response Block,
        then:

        i) IOTP Transaction includes a Brand Dependent Offer Document
           Exchange (see section 9.1.2.1). (Note 2)

     d) Otherwise (Authentication Status IOTP Message of the
        Authentication Document Exchange contains neither a TPO Block
        but nor an Offer Response Block)

        i) IOTP Transaction consists of just an Authentication Document
           Exchange. (Note 3)

  2) Otherwise (no Authentication Request in first IOTP Message):

     e) IOTP Transaction does not include an Authentication Document
        Exchange (Note 2)

     f) If first IOTP Message contains an Offer Response Block, then:

        i) the IOTP Transaction contains a Brand Independent Offer
           Document Exchange (Note 2)

     g) Otherwise (no Offer Response Block in first IOTP Message):

        i) the IOTP Transaction includes a Brand Dependent Offer
           Document Exchange (Note 2)

  3) If an Offer Response Block exists in any IOTP message then:

     h) If the Offer Response Block contains a Delivery Component then:

        i) If the DelivAndPayResp attribute of the Delivery Component
           is set to True, then:




Burdett                      Informational                    [Page 232]

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           (1) the IOTP Transaction consists of a Payment And Delivery
               Document Exchange (see section 9.1.5) (Note 4)

       ii) otherwise (the DelivAndPayResp attribute of the Delivery
           Component is set to False)

           (1) the IOTP Transaction consists of a Payment Document
               Exchange (see section 9.1.3) followed by a Delivery
               Document Exchange (see section 9.1.4) (Note 4)

     i) otherwise (the Offer Response Block does not contain a Delivery
        Component)

        i) if the Offer Response Block contains just one Payment
           Component, then:

           (1) the IOTP Transaction contains just one Payment Document
               Exchange (Note 5)

       ii) if the Offer Response Block contains two Payment Components,
           then:

           (1) the IOTP Transaction contains two Payment Document
               Exchanges.  The StartAfter attribute of the Payment
               Components is used to indicate which payment occurs
               first (Note 6)

      iii) if the Offer Response Block contains no or more than two
           Payment Components, then there is an error

  4) Otherwise (no Offer Response Block) there is an error.

  The following table indicates the types of IOTP Transactions which
  can validly have the conditions indicated above.

  Note                     IOTP Transaction Validity

  1. Any Payment and Authentication IOTP Transaction

  2. Any Payment and Authentication IOTP Transaction except Baseline
     Authentication

  3. Either Baseline Authentication, or a Baseline Purchase, Refund,
     Deposit, Withdrawal or Value Exchange with a failed Authentication

  4. Baseline Purchase only

  5. Baseline Purchase, Refund, Deposit or Withdrawal



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  6. Baseline Value Exchange only

9.1.13 Combining Authentication Transactions with other Transactions

  In the previous sections an Authentication Document Exchange is shown
  preceding an Offer Document Exchange as part of a single IOTP
  Transaction with the same IOTP Transaction Id.

  It is also possible to run a separate Authentication Transaction at
  any point, even in parallel with another IOTP Transaction. Typically
  this will be used:

  o  by a Consumer to authenticate a Merchant, Payment Handler or a
     Delivery Handler, or

  o  by a Payment Handler or Delivery Handler to authenticate a
     Consumer.

  In outline the basic process consists of:

  o  the Trading Role that decides it wants to carry out an
     authentication of another role suspends the current IOTP
     transaction being carried out

  o  a stand-alone Authentication transaction is then carried out. This
     may, at implementer's option, be linked to the original IOTP
     Transaction using a Related To Component (see section 3.3.3) in
     the Transaction Reference Block.

  o  if the Authentication transaction is successful, then the original
     IOTP Transaction is restarted

  o  if the Authentication fails then the original IOTP Transaction is
     cancelled.

  For example, a Consumer could:

  o  authenticate the Payment Handler for a Payment between receiving
     an Offer Response from a Merchant and before sending the Payment
     Request to that Payment Handler

  o  authenticate a Delivery Handler for a Delivery between receiving
     the Payment Response from a Payment Handler and before sending the
     Delivery Request

  A Payment Handler could authenticate a Consumer after receiving the
  Payment Request and before sending the next Payment related message.




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  A Delivery Handler could authenticate a Consumer after receiving the
  Delivery Request and before sending the Delivery Response.

  Note: Some Payment Methods may carry out an authentication within the
  Payment Exchange. In this case the information required to carry out
  the authentication will be included in Payment Scheme Components.

  In this instance IOTP aware application will not be aware that an
  authentication has occurred since the Payment Scheme Components that
  contain authentication request information will be indistinguishable
  from other Payment Scheme Components.

9.2 Infrastructure Transactions

  Infrastructure Transactions are designed to support inquiries about
  whether or not a transaction has succeeded or a Trading Role's
  servers are operating correctly. There are two types of transaction:

  o  a Transaction Status Inquiry Transaction which provides
     information on the status of an existing or complete IOTP
     transaction, and

  o  Ping Transaction that enables one IOTP aware application to
     determine if the IOTP aware application at another Trading Role is
     operating and verify whether or not signatures can be handled.

  Each of these is described below

9.2.1 Baseline Transaction Status Inquiry IOTP Transaction

  The Baseline IOTP Transaction Status Inquiry provides information on
  the status of an existing or complete IOTP transaction.

  The Trading Blocks used by the Baseline Transaction Status Inquiry
  Transaction are:

  o  an Inquiry Request Trading Block (see section 8.12),

  o  an Inquiry Response Trading Block (see section 8.13)

  o  an optional Signature Block (see section 8.16).

  The Inquiry IOTP Transaction can be used for a variety of reasons.
  For example:

  o  to help in resuming a suspended transaction to determine the
     current state of processing of one of the other roles,




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  o  for a merchant to determine if a payment, delivery, etc., was
     completed.  For example, a Consumer might claim that payment was
     made but no signed IOTP payment receipt was available to prove it.
     If the Merchant makes an inquiry of the Payment Handler then the
     Merchant can determine whether or not payment was made.

  Note: Inquiries on Baseline Ping IOTP Transactions (see section
  9.2.2) are ignored.

  MAKING INQUIRIES OF ANOTHER TRADING ROLE

  One Trading Role may make an inquiry of any other Trading Role at any
  point in time.

  IOTP aware software that supports the Consumer Trading Role may not:

  o  digitally sign a response if requested, since it may not have the
     capability, or

  o  respond to an Inquiry Request at all since it may not be on-line,
     or may consider that the request is not reasonable since, for
     example, the Request was not digitally signed.

  As a guideline:

  o  the Consumer should send a Transaction Status Inquiry Block to a
     Trading Role only after the following events have occurred:

     - to the Merchant, after sending a TPO Selection Block,

     - to the Payment Handler, after sending a Payment Request Block,

     - to the Delivery Handler, after sending a Delivery Request Block,

  o  other Trading Roles should send a Transaction Status Inquiry Block
     to the Consumer only after receiving a message from the Consumer
     and before sending the final "Response" message to the Consumer

  o  there are no restrictions on non-Consumer Trading Roles sending
     Inquiries to other trading roles.

  TRANSACTION STATUS INQUIRY TRANSPORT SESSION

  For a Transaction Status Inquiry on an ongoing transaction a
  different transport session from the ongoing transaction is used. For
  a Transaction Status Inquiry on a past transaction, how the IOTP





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  module on the software at the Trading Role is started upon the
  receipt of Inquiry Request message is defined in each Mapping to
  Transport supplement for IOTP.

  TRANSACTION STATUS INQUIRY ERROR HANDLING

  Errors in a Transaction Status Inquiry can be categorised into one of
  the following three cases:

  o  Business errors (see section 4.2) in the original (inquired)
     messages

  o  Technical errors (see section 4.1) - both IOTP and payment scheme
     specific ones - in the original IOTP (inquired) messages

  o  Technical errors in the message containing the Inquiry Request
     Block itself

  The following outlines what the software should do in each case

  BUSINESS ERRORS IN THE ORIGINAL MESSAGES

  Return an Inquiry Response Block containing the Status Component
  which was last sent to the Consumer Role.

  TECHNICAL ERRORS IN THE ORIGINAL MESSAGES

  Return an Inquiry Response Block containing a Status Component. The
  Status Component should contain a ProcessState attribute set to
  ProcessError. In this case send back an Error Block indicating where
  the error was found in the original message.

  TECHNICAL ERRORS IN THE INQUIRY REQUEST BLOCK

  Return an Error message. That is, send back an Error Block containing
  the Error Code (see section 7.21.2) which describes the nature of the
  error in the Inquiry Request message.

  INQUIRY TRANSACTION MESSAGES

  The following Figure outlines the Baseline IOTP Transaction Status
  Inquiry process.









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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*

  1st Role
    |  2nd Role
STEP |     |
1.          The first role decides to inquire on an IOTP Transaction
            by, for example, clicking on the inquiry button of an
            IOTP Aware Application. This will then generate an
            Inquiry Request Block and send it to the appropriate
            Trading Role.

    1 --> 2 INQUIRY REQUEST. IotpMsg: TransRef Block; Signature Block
            (optional); Inquiry Request Block

2.          The Trading Role checks the digital signature (if
            present). If the recipient wants to respond, then the
            Trading Role checks the transaction status of the
            transaction that is being inquired upon by using the
            IotpTransId in the Transaction ID Component of the
            Transaction Reference Block, then generates the
            appropriate Inquiry Response Block, sends the message
            back to the 1st Role and stops

    1 <-- 2 INQUIRY RESPONSE. IotpMsg: TransRef Block; Inquiry
            Response Block; Signature Block (Optional)

3.           First role checks the Inquiry Response Block and optional
            signature, takes whatever action is appropriate or
            perhaps stops. This may include displaying status
            information to the end user.

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

               Figure 32 Baseline Transaction Status Inquiry


  The remainder of this sub-section on the Baseline Transaction Status
  Inquiry IOTP Transaction defines the contents of each Trading Block.
  Note that the term "original transaction" is the transaction which a
  trading role wants to discover some information about.

  TRANSACTION REFERENCE BLOCK

  A Trading Role making an inquiry must use a Transaction Id Component
  (see section 3.3.1) where both the IotpTransId and TransTimeStamp
  attributes are the same as in the Transaction Id Component of the
  original transaction that is being inquired upon. The IotpTransId
  attribute in this component serves as the key in querying the



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  transaction logs maintained at the Trading Role's site. The value of
  the ID attribute of the Message Id Component should be different from
  those of any in the original transaction (see section 3.4.1).

  If up-to-date status information is required then the MsgId
  Component, and in particular the ID attribute for the MsgId Component
  must be different from any other IOTP Message that has been sent by
  the Trading Role. This is required because of the way that
  Idempotency is handled by IOTP (see section 4.5.2.2 Checking/Handling
  Duplicate Messages).

  INQUIRY REQUEST BLOCK

  The Inquiry Request Block (see section 8.12) contains the following
  components:

  o  one Inquiry Type Component (see section 7.18). This identifies
     whether the inquiry is on an offer, payment, or delivery.

  o  zero or one Payment Scheme Components (see section 7.10). This is
     for encapsulating payment scheme specific inquiry messages for
     inquiries on a payment.

  SIGNATURE BLOCK (INQUIRY REQUEST)

  If a signature block is present on the message containing the Inquiry
  Request Block then it may be checked to determine if the Inquiry
  Request is authorised.

  If present, the Inquiry Request Signature Block (see section 8.12)
  contains the following components:

  o  one Signature Component (see section 7.19)

  o  one or more Certificate Components, if required.

  Inquiry Response Blocks should only be generated if the Transaction
  is authorised.

  Note: Digital signatures on an Inquiry Request is only likely to
  occur if the recipient of the request expects the Inquiry Request to
  be signed. In this version of IOTP this will require some kind of
  pre-existing agreement. This means that:

  o  Consumers are unlikely to generate requests with signatures,
     although it is not an error if they do





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  o  the other trading roles may agree that digital signatures are
     required. For example a Payment Handler may require that an
     Inquiry Request is digitally signed by the Merchant so that they
     can check that the request is valid.

  On the other hand if the original transaction to which the Inquiry
  relates was carried out over a secure channel (e.g., [SSL]) then it
  is probably reasonable to presume that if the sender of the Inquiry
  knows the Transaction Id component of the original message (including
  for example the timestamp) then the inquiry is likely to be genuine.

  INQUIRY RESPONSE BLOCK

  The Inquiry Response Block (see section 8.13) contains the following
  components:

  o  one Status Component (see section 7.16). This component holds the
     status information on the inquired transaction,

  o  zero or one Payment Scheme Components. These contain encapsulated
     payment scheme specific inquiry messages for inquiries on payment.

  SIGNATURE BLOCK (INQUIRY RESPONSE)

  If a signature block is present on the message containing the Inquiry
  Response Block then it may be checked by the receiver of the block to
  determine if the Inquiry Response is valid.

  If present, the Inquiry Response Signature Block (see section 8.13)
  contains the following components:

  o one Signature Component (see section 7.19)

  o one or more Certificate Components, if required.

  Note: Digital signatures on an Inquiry Response is only likely to
  occur if the recipient of the response expects the Inquiry Request to
  be signed. In this version of IOTP this will require some kind of
  pre-existing agreement. This means that:

  o  Consumers are unlikely to generate responses with signatures,
     although it is not an error if they do

  o  the other trading roles may agree that digital signatures are
     required. For example a Merchant may require that an Inquiry
     Response is digitally signed by the Payment Handler so that they
     can check that the request response is valid.




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9.2.2 Baseline Ping IOTP Transaction

  The purpose of the Baseline IOTP Ping Transaction is to test basic
  connectivity between the Trading Roles that may take part in an IOTP
  Transaction.

  It enables IOTP aware application software to:

  o  determine if the IOTP aware application at another Trading Role is
     operating, and

  o  verify whether or not the two trading roles signatures can be
     processed.

  For example it can be used by a Merchant to determine if a Payment
  Handler or Delivery Handler is up and running prior to starting a
  Purchase transaction that uses those trading roles.

  The Trading Blocks used by the Baseline Ping IOTP Transaction are:

  o a Ping Request Block (see section 8.14)

  o a Ping Response Block (see section 8.15), and

  o a Signature Block (see section 8.16).

  PING MESSAGES

  The following figure outlines the message flows in the Baseline IOTP
  Ping Transaction.





















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*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*+*
   1st Role
    |  2nd Role
STEP |     |
1.          The IOTP Aware Application in the first Trading Role
            decides to check whether the counterparty IOTP
            application is up and running. It generates a Ping
            Request Block and optional Signature Block and sends them
            to the second trading role.

    1 --> 2 PING REQUEST. IotpMsg: Trans Ref Block; Signature Block
            (Optional); Ping Request Block

2.          The second Trading Role which receives the Ping Request
            Block generates a Ping Response Block and sends it back
            to the sender of the original Ping Request with a
            signature block if required.

    1 <-- 2 PING Response. IotpMsg: Trans Ref Block; Signature Block
            (Optional); Ping Response Block

3.          The first Trading Role checks the Ping Response Block and
            takes appropriate action, if necessary

*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*

                     Figure 33 Baseline Ping Messages

  The verification that signatures can be handled is indicated by the
  sender of the Ping Request Block including:

  o  Organisation Components that identify itself and the intended
     recipient of the Ping Request Block, and

  o  a Signature Block that signs data in the Ping Request.

  In this way the receiver of the Ping Request:

  o  knows who is sending the Ping Request and can therefore verify the
     Signature on the Request, and

  o  knows who to generate a signature for on the Ping Response.

  Note that a Ping Request:

  o  does not affect any on-going transaction





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  o  does NOT initiate an IOTP transaction, unlike other IOTP
     transaction messages such as TPO or Transaction Status Inquiry.

  All IOTP aware applications must return a Ping Response message to
  the sender of a Ping Request message when it is received.

  A Baseline IOTP Ping request can also contain an optional Signature
  Block. IOTP aware applications can, for example, use the Signature
  Block to check the recipient of a Ping Request can successfully
  process and check signatures it has received.

  For each Baseline Ping IOTP Transaction, each IOTP role shall
  establish a different transport session from other IOTP transactions.

  Any IOTP Trading Role can send a Ping request to any other IOTP
  Trading Role at any time it wants. A Ping message has its own
  IotpTransId, which is different from other IOTP transactions.

  The remainder of this sub-section on the Baseline Ping IOTP
  Transaction defines the contents of each Trading Block.

  TRANSACTION REFERENCE BLOCK

  The IotpTransId of a Ping transaction should be different from any
  other IOTP transaction.

  PING REQUEST BLOCK

  If the Ping Transaction is anonymous then no Organisation Components
  are included in the Ping Request Block (see section 8.7).

  If the Ping Transaction is not anonymous then the Ping Request Block
  contains Organisation Components for:

  o  the sender of the Ping Request Block, and

  o  the verifier of the Signature Component

  If Organisation Components are present, then it indicates that the
  sender of the Ping Request message has generated a Signature Block.
  The signature block must be verified by the Trading Role that
  receives the Ping Request Block.

  SIGNATURE BLOCK (PING REQUEST)

  The Ping Request Signature Block (see section 8.16) contains the
  following components:




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  o  one Signature Component (see section 7.19)

  o  one or more Certificate Components, if required.

  PING RESPONSE BLOCK

  The Ping Response Block (see section 8.15) contains the following
  component:

  o  the Organisation Component of the sender of the Ping Response
     message

  If the Ping Transaction is not anonymous then the Ping Response
  additionally contains:

  o  copies of the Organisation Components contained in the Ping
     Request Block.

  SIGNATURE BLOCK (PING RESPONSE)

  The Ping Response Signature Block (see section 8.16) contains the
  following components:

  o  one Signature Component (see section 7.19)

  o  one or more Certificate Components, if required.

10. Retrieving Logos

  This section describes how to retrieve logos for display by IOTP
  aware software using the Logo Net Locations attribute contained in
  the Brand Element (see section 7.7.1) and the Organisation Component
  (see section 7.6).

  The full address of a logo is defined as follows:  Logo_address ::=
  Logo_net_location "/" Logo_size Logo_color_depth ".gif"

  Where:

  o  Logo_net_location is obtained from the LogoNetLocn attribute in
     the Brand Element (see section 7.7.1) or the Organisation
     Component. Note that:

     -  the content of this attribute is dependent on the Transport
        Mechanism (such as HTTP) that is used. See the Transport
        Mechanism supplement,





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     -  implementers should check that if the rightmost character of
        Logo Net Location is set to right-slash "/" then another, right
        slash should not be included when generating the Logo Address,

  o  Logo_size identifies the size of the logo,

  o  Logo_color_depth identifies the colour depth of the logo

  o  "gif" indicates that the logos are in "gif" format

  Logo_size and Logo_color_depth are specified by the implementer of
  the IOTP software that is retrieving the logo depending on the size
  and colour that they want to use.

10.1 Logo Size

  There are five standard sizes for logos. The sizes in pixels and the
  corresponding values for Logo Size are given in the table below.

          Size in     Logo Size
          Pixels        Value

       32 x 32 or   exsmall
       32 x 20

       53 x 33      small

       103 x 65     medium

       180 x 114    large

       263 x 166    exlarge

10.2 Logo Color Depth

  There are three standard colour depths. The colour depth (including
  bits per pixel) and the corresponding value for Logo_Color_Depth are
  given in the table below.

               Color Depth          Logo Color
            (bits per pixel)        Depth Value

        4 (16 colors)            4

        8 (256 colors)           nothing

        24 (16 million colors)   24




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  Note that if Logo Color Depth is omitted then a logo with the default
  colour depth of 256 colours will be retrieved.

10.3 Logo Net Location Examples

  If Logo Net Location was set to "ftp://logos.xzpay.com", then:

  o  "ftp://logos.xzpay.com/medium.gif" would retrieve a medium size
     256 colour logo

  o  "http://logos.xzpay.com/small4.gif" would retrieve a small size 16
     colour logo

  Note: Organisations which make logos available for use with IOTP
  should always make available "small" and "medium" size logos and use
  the "gif" format.

11. Brands

  This section contains:

  o  a definition of Brands and an outline of Brand Selection using
     Brand Lists, and

  o  some XML examples of Brand Lists

11.1 Brand Definitions and Brand Selection

  One of the key features of IOTP is the ability for a merchant to
  offer a list of Brands from which a consumer may make a selection.
  This section provides an overview of what is involved and provides
  guidance on how selection of a brand and associated payment
  instrument can be carried out by a Consumer. It covers:

  o  definitions of Payment Instruments and Brands - what are Payment
     Instruments and Brands in an IOTP context. Further categorises
     Brands as optionally a "Dual Brand" or a "Promotional Brand",

  o  identification and selection of Promotional Brands - Promotional
     Brands offer a Consumer some additional benefit, for example
     loyalty points or a discount. This means that both Consumers and
     Merchant must be able to correctly identify that a valid
     Promotional Brand is being used.

  Also see the following sections:






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  o  Brand List Component (section 7.7) which contains definitions of
     the XML elements which contain the list of Brands offered by a
     Merchant to a Consumer, and

  o  Brand Selection Component (section 7.8) for details of how a
     Consumer records the Brand, currency, amount and payment protocol
     that was selected.

11.1.1 Definition of Payment Instrument

  A Payment Instrument is the means by which a Consumer pays for goods
  or services offered by a Merchant. It can be, for example:

  o  a credit card such as MasterCard or Visa;

  o  a debit card such as MasterCard's Maestro;

  o  a smart card based electronic cash payment instrument such as a
     Mondex Card, a GeldKarte card or a Visa Cash card

  o  a software based electronic payment account such as a CyberCash or
     DigiCash account.

  Most Payment Instruments have a number, typically an account number,
  by which the Payment Instrument can be identified.

11.1.2 Definition of Brand

  A Brand is the mark which identifies a particular type of Payment
  Instrument. A list of Brands are the payment options which are
  presented by the Merchant to the Consumer and from which the Consumer
  makes a selection. Each Brand may have a different Payment Handler.
  Examples of Brands include:

  o  payment association and proprietary Brands, for example
     MasterCard, Visa, American Express, Diners Club, Mondex,
     GeldKarte, CyberCash, etc.

  o  promotional brands (see below). These include:

     -  store brands, where the Payment Instrument is issued to a
        Consumer by a particular Merchant, for example Walmart, Sears,
        or Marks and Spencer (UK)

     -  cobrands, for example American Advantage Visa, where an
        Organisation uses their own brand in conjunction with,
        typically, a payment association Brand.




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11.1.3 Definition of Dual Brand

  A Dual Brand means that a single payment instrument may be used as if
  it were two separate Brands. For example there could be a single
  Japanese "UC" MasterCard which can be used as either a UC card or a
  regular MasterCard. The UC card Brand and the MasterCard Brand could
  each have their own separate Payment Handlers. This means that:

  o  the merchant treats, for example "UC" and "MasterCard" as two
     separate Brands when offering a list of Brands to the Consumer,

  o  the consumer chooses a Brand, for example either "UC" or
     "MasterCard,

  o  the consumer IOTP aware application determines which Payment
     Instrument(s) match the chosen Brand, and selects, perhaps with
     user assistance, the correct Payment Instrument to use.

  Note: Dual Brands need no special treatment by the Merchant and
  therefore no explicit reference is made to Dual Brands in the DTD.
  This is because, as far as the Merchant is concerned, each Brand in a
  Dual Brand is treated as a separate Brand. It is at the Consumer,
  that the matching of a Brand to a Dual Brand Payment Instrument needs
  to be done.

11.1.4 Definition of Promotional Brand

  A Promotional Brand means that, if the Consumer pays with that Brand,
  then the Consumer will receive some additional benefit which can be
  received in two ways:

  o  at the time of purchase. For example if a Consumer pays with a
     "Walmart MasterCard" at a Walmart web site, then a 5% discount
     might apply, which means the consumer actually pays less,

  o  from their Payment Instrument (card) issuer when the payment
     appears on their statement. For example loyalty points in a
     frequent flyer scheme could be awarded based on the total payments
     made with the Payment Instrument since the last statement was
     issued.

  Note that:

  o  the first example (obtaining the benefit at the time of purchase),
     requires that:

     -  the Consumer is informed of the benefits which arise if that
        Brand is selected



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     -  if the Brand is selected, the Merchant changes the relevant
        IOTP Components in the Offer Response to reflect the correct
        amount to be paid

  o  the second (obtaining a benefit through the Payment Instrument
     issuer) does not require that the Offer Response is changed

  o  each Promotional Brand should be identified as a separate Brand in
     the list of Brands offered by the Merchant. For example:
     "Walmart", "Sears", "Marks and Spencer" and "American Advantage
     Visa", would each be a separate Brand.

11.1.5 Identifying Promotional Brands

  There are two problems which need to handled in identifying
  Promotional Brands:

  o  how does the Merchant or their Payment Handler positively identify
     the promotional brand being used at the time of purchase

  o  how does the Consumer reliably identify the correct promotional
     brand from the Brand List presented by the Merchant

  The following is a description of how this could be achieved.

  Note: Please note that the approach described here is a model
  approach that solves the problem. Other equivalent methods may be
  used.

11.1.5.1 Merchant/Payment Handler Identification of Promotional Brands

  Correct identification that the Consumer is paying using a
  Promotional Brand is important since a Consumer might fraudulently
  claim to have a Promotional Brand that offers a reduced payment
  amount when in reality they do not.

  Two approaches seem possible:

  o  use some feature of the Payment Instrument or the payment method
     to positively identify the Brand being used. For example, the SET
     certificate for the Brand could be used, if one is available, or

  o  use the Payment Instrument (card) number to look up information
     about the Payment Instrument on a Payment Instrument issuer
     database to determine if the Payment Instrument is a promotional
     brand.





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  Note that:

  o  the first assumes that SET is available.

  o  the second is only possible if the Merchant, or alternatively the
     Payment Handler, has access to card issuer information.

  IOTP does not provide the Merchant with Payment Instrument
  information (e.g., a card or account number). This is only sent as
  part of the encapsulated payment protocol to a Payment Handler. This
  means that:

  o  the Merchant would have to assume that the Payment Instrument
     selected was a valid Promotional Brand, or

  o  the Payment Handler would have to check that the Payment
     Instrument was for the valid Promotional Brand and fail the
     payment if it was not.

  A Payment Handler checking that a brand is a valid Promotional Brand
  is most likely if the Payment Handler is also the Card Issuer.

11.1.5.2 Consumer Selection of Promotional Brands

  Two ways by which a Consumer can correctly select a Promotional Brand
  are:

  o  the Consumer visually matching a logo for the Promotional Brand
     which has been provided to the Consumer by the Merchant,

  o  the Consumer's IOTP aware application matching a code for the
     Promotional Brand which the application has registered against a
     similar code contained in the list of Brands offered by the
     Merchant.

  In the latter case, the code contained in the Consumer wallet must
  match exactly the code in the list offered by the Merchant otherwise
  no match will be found. Ways in which the Consumer's IOTP Aware
  Application could obtain such a code include:

  o  the Consumer types the code in directly. This is error prone and
     not user friendly, also the consumer needs to be provided with the
     code.  This approach is not recommended,

  o  using one of the Brand Identifiers defined by IOTP and pre-loaded
     into the Consumers IOTP Aware application or wallet by the
     developer of the Wallet,




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  o  using some information contained in the software or other data
     associated with the Payment Instrument. This could be:

     -  a SET certificate for Brands which use this payment method

     -  a code provided by the payment software which handles the
        particular payment method, this could apply to, for example,
        GeldKarte, Mondex, CyberCash and DigiCash,

  o  the consumer making an initial "manual" link between a Promotional
     Brand in the list of Brands offered by the Merchant and an
     individual Payment Instrument, the first time the promotional
     brand is used. The IOTP Aware application would then "remember"
     the code for the Promotional Brand for use in future purchases.

11.1.5.3 Consumer Software Brand Id recommendation

  New Brand Ids are allocated under IANA procedures (see section 12
  IANA Considerations). Which also contains an initial list of Brand
  Identifiers.

  It is recommended that implementers of consumer IOTP aware
  applications (e.g., software wallets) pre-load their software with
  the then current set of Brand Ids and provide a method by which they
  can be updated. For example, by going to the software developer's web
  site.

11.2 Brand List Examples

  This example contains three examples of the XML for a Brand List
  Component. It covers:

  o  a simple credit card based example

  o  a credit card based brand list including promotional credit card
     brands, and

  o  a complex electronic cash based brand list

  Note that:

  o  brand lists can be as complex or as simple as required

  o  all example techniques described in this appendix can be included
     in one brand list.






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11.2.1 Simple Credit Card Based Example

  This is a simple example involving:

  o  only major credit card payment brands

  o  a single price in a single currency

  o  a single Payment Handler, and

  o  a single payment protocol

  <BrandList ID='M1.2'
    XML:Lang='us-en'
    ShortDesc='Purchase book including s&h'
    PayDirection='Debit' >
    <Brand ID ='M1.30'
      BrandId='MasterCard'
      BrandName='MasterCard Credit'
      BrandLogoNetLocn='ftp://otplogos.mastercard.com/mastercardcredit'
      ProtocolAmountRefs='M1.33'>
    </Brand>
    <Brand ID ='M.31'
      BrandId='Visa'
      BrandName='Visa Credit'
      BrandLogoNetLocn='ftp://otplogos.visa.com/visacredit'
      ProtocolAmountRefs='M1.33'>
    </Brand>
    <Brand ID ='M1.32'
      BrandId='AmericanExpress'
      BrandName='American Express'
      BrandLogoNetLocn='ftp://otplogos.amex.com'
      ProtocolAmountRefs ='M1.33' >
    </Brand >
    <ProtocolAmount ID ='M1.33'
      PayProtocolRef='M1.35'
      CurrencyAmountRefs='M1.34'>
    </ProtocolAmount>
    <CurrencyAmount ID ='M1.34'
      Amount='10.95'
      CurrCode='USD'/>
    <PayProtocol ID ='M1.35'
      ProtocolId='SCCD1.0'
      ProtocolName='Secure Channel Credit/Debit'
      PayReqNetLocn='http://www.example.com/etill/sccd1' >
    </PayProtocol>
  </BrandList>




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11.2.2 Credit Card Brand List Including Promotional Brands

  An example of a Credit Card based Brand List follows. It includes:

  o  two ordinary card association brands and two promotional credit
     card brands. The promotional brands consist of one loyalty based
     (British Airways MasterCard) which offers additional loyalty
     points and one store based (Walmart) which offers a discount on
     purchases over a certain amount

  o  two payment protocols:

     -  SET (Secure Electronic Transactions) see [SET], and

     -  SCCD (Secure Channel Credit Debit) see [SCCD].

<BrandList ID='M1.2'
  XML:Lang='us-en'
  ShortDesc='Purchase ladies coat'
  PayDirection='Debit' >
  <Brand ID ='M1.3'
    BrandId='MasterCard'
    BrandName='MasterCard Credit'
    BrandLogoNetLocn='ftp://otplogos.mastercard.com'
    ProtocolAmountRefs='M1.7 M1.8'>
    <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='MasterCard:'>
    </ProtocolBrand>
  </Brand>
  <Brand ID ='M1.4'
    BrandId='Visa'
    BrandName='Visa Credit'
    BrandLogoNetLocn='ftp://otplogos.visa.com'
    ProtocolAmountRefs='M1.7 M1.8'>
    <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='Visa:'>
    </ProtocolBrand>
  </Brand>
  <Brand ID ='M1.5'
    BrandId='BritishAirwaysMC'
    BrandName='British Airways MasterCard'
    BrandLogoNetLocn='ftp://otplogos.britishairways.co.uk'
    BrandNarrative='Double air miles with British Airways MasterCard'
    ProtocolAmountRefs ='M1.7 M1.8' >
    <ProtocolBrand ProtocolId='SET1.0' ProtocolBrandId='MasterCard:BA'>
    </ProtocolBrand>
  </Brand >
  <Brand ID ='M1.6'
    BrandId='Walmart'
    BrandName='Walmart Store Card'



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    BrandLogoNetLocn='ftp://otplogos.walmart.com'

    BrandNarrative='5% off with your Walmart Card
                  on purchases over $150'
    ProtocolAmountRefs='M1.8'>
  </Brand>
  <ProtocolAmount ID ='M1.7'
    PayProtocolRef='M1.10'
    CurrencyAmountRefs='M1.9' >
    <PackagedContent Transform="BASE64">
       238djqw1298erh18dhoire
    </PackagedContent>
  </ProtocolAmount>
  <ProtocolAmount ID ='M1.8'
    PayProtocolRef='M1.11'
    CurrencyAmountRefs='M1.9' >
    <PackagedContent Transform="BASE64">
       238djqw1298erh18dhoire
    </PackagedContent>
  </ProtocolAmount>
  <CurrencyAmount ID ='M1.9'
    Amount='157.53'
    CurrCode='USD'/>
  <PayProtocol ID ='M1.10'
    ProtocolId='SET1.0'
    ProtocolName='Secure Electronic Transaction Version 1.0'
    PayReqNetLocn='http://www.example.com/etill/set1' >
    <PackagedContent Transform="BASE64">
      8ueu26e482hd82he82
    </PackagedContent>
  </PayProtocol>
  <PayProtocol ID ='M1.11'
    ProtocolId='SCCD1.0'
    ProtocolName='Secure Channel Credit/Debit'
    PayReqNetLocn='http://www.example.com/etill/sccd1' >
    <PackagedContent Transform="BASE64">
       82hd82he8226e48ueu
    </PackagedContent>
  </PayProtocol>
 </BrandList>

11.2.3 Brand Selection Example

  In order to pay by 'British Airways' MasterCard using the example
  above using SET and therefore getting double air miles, the Brand
  Selection would be:

  <BrandSelection ID='C1.2'



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    BrandListRef='M1.3'
    BrandRef='M1.5'
    ProtocolAmountRef='M1.7'
    CurrencyAmountRef='M1.9' >
  </BrandSelection>

11.2.4 Complex Electronic Cash Based Brand List

  The following is an fairly complex example which includes:

  o  payments using either Mondex, GeldKarte, CyberCash or DigiCash

  o  in currencies including US dollars, British Pounds, Italian Lira,
     German Marks and Canadian Dollars

  o  a discount on the price if the payment is made in Mondex using
     British pounds or US dollars, and

  o  more than one Payment Handler is used for payments involving
     Mondex or CyberCash

  o  support for more than one version of a CyberCash CyberCoin payment
     protocol.

  <BrandList ID='M1.2'
    XML:Lang='us-en'
    ShortDesc='Company report on XYZ Co'
    PayDirection='Debit' >
    <Brand ID ='M1.13'
      BrandId='Mondex'
      BrandName='Mondex Electronic Cash'
      BrandLogoNetLocn='ftp://otplogos.mondex.com'
      ProtocolAmountRefs='M1.17 M1.18'>
    </Brand>
    <Brand ID ='M1.14'
      BrandId='GeldKarte'
      BrandName='GeldKarte Electronic Cash'
      BrandLogoNetLocn='ftp://otplogos.geldkarte.co.de'
      ProtocolAmountRefs='M1.19'>
    </Brand>
    <Brand ID ='M1.15'
      BrandId='CyberCoin'
      BrandName='CyberCoin Eletronic Cash'
      BrandLogoNetLocn='http://otplogos.cybercash.com'
      ProtocolAmountRefs ='M1.20' >
    </Brand >
    <Brand ID ='M1.16'
      BrandId='DigiCash'



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      BrandName='DigiCash Electronic Cash'
      BrandLogoNetLocn='http://otplogos.digicash.com'
      BrandNarrative='5% off with your Walmart Card
                    on purchases over $150'
      ProtocolAmountRefs='M1.22'>
    </Brand>
    <ProtocolAmount ID ='M1.17'
      PayProtocolRef='M1.31'
      CurrencyAmountRefs='M1.25 M1.29'>
    </ProtocolAmount>
    <ProtocolAmount ID ='M1.18'
      PayProtocolRef='M1.32'
      CurrencyAmountRefs='M1.26 M1.27 M1.28 M1.30'>
    </ProtocolAmount>
    <ProtocolAmount ID ='M1.19'
      PayProtocolRef='M1.35'
      CurrencyAmountRefs='M1.28'>
    </ProtocolAmount>
    <ProtocolAmount ID ='M1.20'
      PayProtocolRef='M1.34 M1.33'
      CurrencyAmountRefs='M1.23 M1.24 M1.27 M1.28 M1.29 M1.30'>
    </ProtocolAmount>
    <ProtocolAmount ID ='M1.21'
      PayProtocolRef='M1.36'
      CurrencyAmountRefs='M1.23 M1.24 M1.27 M1.28 M1.29 M1.30'>
    </ProtocolAmount>
    <CurrencyAmount ID ='M1.23'
      Amount='20.00'
      CurrCode='USD'/>
    <CurrencyAmount ID ='M1.24'
      Amount='12.00'
      CurrCode='GBP'/>
    <CurrencyAmount ID ='M1.25'
      Amount='19.50'
      CurrCode='USD'/>
    <CurrencyAmount ID ='M1.26'
      Amount='11.75'
      CurrCode='GBP'/>
    <CurrencyAmount ID ='M1.27'
      Amount='36.00'
      CurrCode='DEM'/>
    <CurrencyAmount ID ='M1.28'
      Amount='100.00'
      CurrCode='FFR'/>
    <CurrencyAmount ID ='M1.29'
      Amount='22.00'
      CurrCode='CAD'/>
    <CurrencyAmount ID ='M1.30'



Burdett                      Informational                    [Page 256]

RFC 2801                       IOTP/1.0                       April 2000


      Amount='15000'
      CurrCode='ITL'/>
    <PayProtocol ID ='M1.31'
      ProtocolId='MXv1.0'
      ProtocolName='Mondex IOTP Protocol Version 1.0'
      PayReqNetLocn='http://www.mxbankus.com/etill/mx' >
    </PayProtocol>
    <PayProtocol ID ='M1.32'
      ProtocolId='MXv1.0'
      ProtocolName='Mondex IOTP Protocol Version 1.0'
      PayReqNetLocn='http://www.mxbankuk.com/vserver' >
    </PayProtocol>
    <PayProtocol ID ='M1.33'
      ProtocolId='Ccashv1.0'
      ProtocolName='CyberCoin Version 1.0'
      PayReqNetLocn='http://www.cybercash.com/ccoin' >
    </PayProtocol>
    <PayProtocol ID ='M1.34'
      ProtocolId='CCashv2.0'
      ProtocolName='CyberCoin Version 2.0'
      PayReqNetLocn='http://www.cybercash.com/ccoin' >
    </PayProtocol>
    <PayProtocol ID ='M1.35'
      ProtocolId='GKv1.0'
      ProtocolName='GeldKarte Version 1.0'
      PayReqNetLocn='http://www.example.com/pgway' >
    </PayProtocol>
    <PayProtocol ID ='M1.36'
      ProtocolId='DCashv1.0'
      ProtocolName='DigiCash Protocol Version 1.0'
      PayReqNetLocn='http://www.example.com/digicash' >
    </PayProtocol>
    </BrandList>

12. IANA Considerations

  This section describes the codes that are controlled by IANA, and
  also how new codes can be created for testing purposes that are not
  controlled by IANA.

12.1 Codes Controlled by IANA

  To help ensure interoperability, there is a need for codes used by
  IOTP to be maintained in a controlled environment so that their
  meaning and usage are well defined and duplicate codes avoided.
  [IANA] is the mechanism to be used for this purpose as described in
  RFC 2434.




Burdett                      Informational                    [Page 257]

RFC 2801                       IOTP/1.0                       April 2000


  The element types and attributes names to which this procedure
  applies is shown in the table below together with the initial values
  that are valid for these attributes.

  Note that:

  o  the IETF Trade mailing list's email address is ietf-
     [email protected]

  o  "Designated Experts" (see [IANA]) are appointed by the IESG.

    Element Type/                     Attribute Values
    Attribute Name

  Algorithm/         "sha1" - indicates that a [SHA1] authentication
  Name               will apply
  (When Algorithm
  is a child of an   "signature" - indicates that authentication
  AuthReq            consists of the generation of a digital signature.
  Component)
                     "Pay:ppp" where "ppp" may be set to any valid
                     value for "iotpbrand" (see below)

                     With the exception of Algorithms that begin with
                     "pay:", new values are allocated following review
                     on the IETF Trade mailing list and by the
                     Designated Expert.

  Note:     The Algorithm element is likely to be eventually defined
  within the [DSIG] name space. It is likely that the maintenance
  procedure defined here may need to vary over time, as the DSIG
  proposals become more widely adopted.

    Element Type/                     Attribute Values
    Attribute Name

  Brand/BrandId      The following list of initial BrandIds have been
                     taken from those Organisations that have applied
                     for SET certificates as at 1st June 1999:

                     "Amex" - American Express

                     "Dankort" - Dankort

                     "JCB" - JCB

                     "Maestro" - Maestro




Burdett                      Informational                    [Page 258]

RFC 2801                       IOTP/1.0                       April 2000


                     "MasterCard" - MasterCard

                     "NICOS" - NICOS

                     "VISA" - Visa

                     In addition the following Brand Id values are
                     defined:

                     "Mondex"

                     "GeldKarte"

                     New values of BrandId must be announced to the
                     IETF Trade mailing list and, if there are no
                     objections within three weeks, are allocated on a
                     "first come first served" basis.

  CurrencyAmount/    Currency codes are dependent on CurrCodeType (see
  CurrCode           below).

                     If CurrCodeType is "ISO4217-A" then the currency
                     code is an alphabetic currency code as defined by
                     [ISO4217].

                     If CurrCodeType is "IOTP" then new values must be
                     announced to the IETF Trade mailing list and, if
                     there are no objections within three weeks, are
                     allocated on a "first come first served" basis.

  Note:     The Currency Code Type of IOTP, is designed to allow the
  support of "new" psuedo currencies such as loyalty or frequent flyer
  points. At the time of writing this specification, no currency codes
  of this type have been defined.

    Element Type/                     Attribute Values
    Attribute Name

  CurrencyAmount/    "ISO4217-A"
  CurrCodeType
                     "IOTP"

                     New values of CurrCodeType attribute are allocated
                     following review on the IETF Trade mailing list
                     and by the Designated Expert.

  DeliveryData/      "Post"
  DelivMethod



Burdett                      Informational                    [Page 259]

RFC 2801                       IOTP/1.0                       April 2000


                     "Web"

                     "Email"

                     New values of Delivery Method attribute are
                     allocated following review on the IETF Trade
                     mailing list and by the Designated Expert. This
                     may require the publication of additional
                     documentation to describe how the delivery method
                     is used.

  PackagedContent/   "PCDATA"
  Content
                     "MIME"

                     "MIME:mimetype" (where mimetype must be the same
                     as content-type as defined by [MIME] )

                     "XML"

                     If the Content attribute is of the form
                     "MIME"mimetype", then control of new values for
                     "mimetype" is as defined in [MIME].

                     Otherwise, new values of the Content attribute are
                     allocated following review on the IETF Trade
                     mailing list and by the Designated Expert. This
                     may require the publication of additional
                     documentation to describe how the new attribute is
                     used within a Packaged Content element.

  RelatedTo/         "IotpTransaction"
  RelationshipType
                     "Reference"

                     New values of the RelationshipType attribute are
                     allocated following review on the IETF Trade
                     Working Group mailing list and by the Designated
                     Expert. This may require the publication of
                     additional documentation to describe how the

    Element Type/                     Attribute Values
    Attribute Name
                     delivery method is used.

  Status/            Offer
  StatusType
                     Payment



Burdett                      Informational                    [Page 260]

RFC 2801                       IOTP/1.0                       April 2000


                     Delivery

                     Authentication

                     Unidentified

                     New values of the Status Type attribute are
                     allocated following:
                      o publication to the IETF Trade Working Group,
                        of an RFC describing the Trading Exchange,
                        Trading Roles and associated components that
                        relate to the Status, and
                      o review of the document on the IETF Trade
                        mailing list and by the Designated Expert.

  Note: The document describing new values for the Status Type
  attribute may be combined with documents that describe new Trading
  Roles and types of signatures (see below).

  TradingRole/       "Consumer"
  TradingRole
                     "Merchant"

                     "PaymentHandler"

                     "DeliveryHandler"

                     "DelivTo"

                     "CustCare"

                     New values of the Trading Role attribute are
                     allocated following:
                      o publication to the IETF Trade Working Group,
                        of an RFC describing the Trading Exchange,
                        Trading Roles and associated components that
                        relate to the Trading Role, and
                      o review of the document on the IETF Trade
                        mailing list and by the Designated Expert.

  Note: The document describing new values for the Trading Role
  attribute may be

    Element Type/                     Attribute Values
    Attribute Name
                                  combined with documents that describe
                                  new Status Types (see above) and
                                  types of signatures (see below).



Burdett                      Informational                    [Page 261]

RFC 2801                       IOTP/1.0                       April 2000


  TransId/           "BaselineAuthentication"
  IotpTransType
                     "BaselineDeposit"

                     "BaselinePurchase"

                     "BaselineRefund"

                     "BaselineWithdrawal"

                     "BaselineValueExchange"

                     "BaselineInquiry"

                     "BaselinePing"

                     New values of the IotpTransType attribute are
                     allocated following:
                      o publication to the IETF Trade mailing list, of
                        an RFC describing the new IOTP Transaction, and
                      o review of the document on the IETF Trade
                        Working Group mailing list and by the
                        Designated Expert.

  Attribute/ Content
  (see Signature
                     "OfferResponse"
  Component)         "PaymentResponse"

                     "DeliveryResponse"

                     "AuthenticationRequest"

                     "AuthenticationResponse"

                     "PingRequest"

                     "PingResponse"

                     New values of the code that define the type of a
                     signature are allocated following:
                      o publication to the IETF Trade Working Group,
                        of an RFC describing the Trading Exchange where
                        the signature is being used, and
                      o review of the document on the IETF Trade
                        mailing list and by the Designated Expert.





Burdett                      Informational                    [Page 262]

RFC 2801                       IOTP/1.0                       April 2000


    Element Type/                     Attribute Values
    Attribute Name

  Note: The document describing new values for the types of signatures
  may be combined with documents that describe new Status Types and
  Trading Roles (see above).

12.2 Codes not controlled by IANA

  In addition to the formal development and registration of codes as
  described above, there is still a need for developers to experiment
  using new IOTP codes. For this reason, "user defined codes" may be
  used to identify additional values for the codes contained within
  this specification without the need for them to be registered with
  IANA.

  The definition of a user defined code is as follows:

  user_defined_code ::= ( "x-" | "X-" ) NameChar (NameChar)*

    NameChar           NameChar has the same definition as the [XML]
                       definition of NameChar

  Use of domain names (see [DNS]) to make user defined codes unique is
  recommended although this method cannot be relied upon.

13. Internet Open Trading Protocol Data Type Definition

  This section contains the XML DTD for the Internet Open Trading
  Protocols.





















Burdett                      Informational                    [Page 263]

RFC 2801                       IOTP/1.0                       April 2000


  <!--
  ******************************************************
  *                                                    *
  * INTERNET OPEN TRADING PROTOCOL VERSION 1.0 DTD     *
  * Filename: ietf.org/rfc/rfc2801.dtd                 *
  *                                                    *
  * Changes from version 07 (iotp-v1.0-protocol-07.dtd)*
  *   - NO CHANGES                                     *
  *                                                    *
  *                                                    *
  *                                                    *
  *                                                    *
  * Copyright Internet Engineering Task Force 1998-2000*
  *                                                    *
  ******************************************************

  ******************************************************
  * IOTP MESSAGE DEFINITION                            *
  ******************************************************
   -->

  <!ELEMENT IotpMessage
     ( TransRefBlk,
       IotpSignatures?,
       ErrorBlk?,
       ( AuthReqBlk |
         AuthRespBlk |
         AuthStatusBlk |
         CancelBlk |
         DeliveryReqBlk |
         DeliveryRespBlk |
         InquiryReqBlk |
         InquiryRespBlk |
         OfferRespBlk |
         PayExchBlk |
         PayReqBlk |
         PayRespBlk |
         PingReqBlk |
         PingRespBlk |
         TpoBlk |
         TpoSelectionBlk
       )*
     ) >
  <!ATTLIST IotpMessage
    xmlns              CDATA
     'iotp:ietf.org/iotp-v1.0' >





Burdett                      Informational                    [Page 264]

RFC 2801                       IOTP/1.0                       April 2000


  <!--
  ******************************************************
  * TRANSACTION REFERENCE BLOCK DEFINITION             *
  ******************************************************
   -->

  <!ELEMENT TransRefBlk (TransId, MsgId, RelatedTo*) >
  <!ATTLIST TransRefBlk
   ID                 ID      #REQUIRED >


  <!ELEMENT TransId EMPTY >
  <!ATTLIST TransId
   ID                 ID      #REQUIRED
   Version            NMTOKEN #FIXED '1.0'
   IotpTransId        CDATA   #REQUIRED
   IotpTransType      CDATA   #REQUIRED
   TransTimeStamp     CDATA   #REQUIRED >


  <!ELEMENT MsgId EMPTY >
  <!ATTLIST MsgId
   ID                 ID      #REQUIRED
   RespIotpMsg        NMTOKEN #IMPLIED
   xml:lang           NMTOKEN #REQUIRED
   LangPrefList       NMTOKENS #IMPLIED
   CharSetPrefList    NMTOKENS #IMPLIED
   SenderTradingRoleRef NMTOKEN #IMPLIED
   SoftwareId         CDATA   #REQUIRED
   TimeStamp          CDATA   #IMPLIED >


  <!ELEMENT RelatedTo (PackagedContent) >
  <!ATTLIST RelatedTo
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   RelationshipType   NMTOKEN #REQUIRED
   Relation           CDATA   #REQUIRED
   RelnKeyWords       NMTOKENS #IMPLIED >



  <!--
  ******************************************************
  * Packaged Content Common Element                    *
  ******************************************************
   -->




Burdett                      Informational                    [Page 265]

RFC 2801                       IOTP/1.0                       April 2000


  <!ELEMENT PackagedContent (#PCDATA) >
  <!ATTLIST PackagedContent
   Name             CDATA     #IMPLIED
   Content          NMTOKEN   "PCDATA"
   Transform (NONE|BASE64)    "NONE" >

  <!--
  ******************************************************
  * TRADING COMPONENTS                                 *
  ******************************************************
   -->
  <!-- PROTOCOL OPTIONS COMPONENT -->
  <!ELEMENT ProtocolOptions EMPTY >
  <!ATTLIST ProtocolOptions
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   SenderNetLocn      CDATA   #IMPLIED
   SecureSenderNetLocn CDATA  #IMPLIED
   SuccessNetLocn     CDATA   #REQUIRED >


  <!-- AUTHENTICATION DATA COMPONENT -->
  <!ELEMENT AuthReq (Algorithm, PackagedContent*)>
  <!ATTLIST AuthReq
   ID                 ID      #REQUIRED
   AuthenticationId   CDATA   #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- AUTHENTICATION RESPONSE COMPONENT -->
  <!ELEMENT AuthResp (PackagedContent*) >
  <!ATTLIST AuthResp
   ID                 ID      #REQUIRED
   AuthenticationId   CDATA   #REQUIRED
   SelectedAlgorithmRef NMTOKEN #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!-- TRADING ROLE INFO REQUEST COMPONENT -->
  <!ELEMENT TradingRoleInfoReq EMPTY>
  <!ATTLIST TradingRoleInfoReq
   ID                 ID      #REQUIRED
   TradingRoleList    NMTOKENS #REQUIRED >

  <!-- ORDER COMPONENT -->
  <!ELEMENT Order (PackagedContent*) >
  <!ATTLIST Order
   ID                 ID      #REQUIRED



Burdett                      Informational                    [Page 266]

RFC 2801                       IOTP/1.0                       April 2000


   xml:lang           NMTOKEN #REQUIRED
   OrderIdentifier    CDATA   #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   ApplicableLaw      CDATA   #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!-- ORGANISATION COMPONENT -->
  <!ELEMENT Org (TradingRole+, ContactInfo?,
       PersonName?, PostalAddress?)>
  <!ATTLIST Org
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   OrgId              CDATA   #REQUIRED
   LegalName          CDATA   #IMPLIED
   ShortDesc          CDATA   #IMPLIED
   LogoNetLocn        CDATA   #IMPLIED >


  <!ELEMENT TradingRole EMPTY >
  <!ATTLIST TradingRole
   ID      ID#REQUIRED
   TradingRole        NMTOKEN #REQUIRED
   IotpMsgIdPrefix    NMTOKEN #REQUIRED
   CancelNetLocn      CDATA   #IMPLIED
   ErrorNetLocn       CDATA   #IMPLIED
   ErrorLogNetLocn  CDATA           #IMPLIED >


  <!ELEMENT ContactInfo EMPTY >
  <!ATTLIST ContactInfo
   xml:lang           NMTOKEN #IMPLIED
   Tel                CDATA   #IMPLIED
   Fax                CDATA   #IMPLIED
   Email              CDATA   #IMPLIED
   NetLocn            CDATA   #IMPLIED >


  <!ELEMENT PersonName EMPTY >
  <!ATTLIST PersonName
   xml:lang           NMTOKEN #IMPLIED
   Title              CDATA   #IMPLIED
   GivenName          CDATA   #IMPLIED
   Initials           CDATA   #IMPLIED
   FamilyName         CDATA   #IMPLIED >





Burdett                      Informational                    [Page 267]

RFC 2801                       IOTP/1.0                       April 2000


  <!ELEMENT PostalAddress EMPTY >
  <!ATTLIST PostalAddress
   xml:lang           NMTOKEN #IMPLIED
   AddressLine1       CDATA   #IMPLIED
   AddressLine2       CDATA   #IMPLIED
   CityOrTown         CDATA   #IMPLIED
   StateOrRegion      CDATA   #IMPLIED
   PostalCode         CDATA   #IMPLIED
   Country            CDATA   #IMPLIED
   LegalLocation (True | False) 'False' >


  <!-- BRAND LIST COMPONENT -->
  <!ELEMENT BrandList (Brand+, ProtocolAmount+,
   CurrencyAmount+, PayProtocol+) >
  <!ATTLIST BrandList
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ShortDesc          CDATA   #REQUIRED
   PayDirection (Debit | Credit) #REQUIRED >

  <!ELEMENT Brand (ProtocolBrand*, PackagedContent*) >
  <!ATTLIST Brand
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #IMPLIED
   BrandId            CDATA   #REQUIRED
   BrandName          CDATA   #REQUIRED
   BrandLogoNetLocn   CDATA   #REQUIRED
   BrandNarrative     CDATA   #IMPLIED
   ProtocolAmountRefs IDREFS  #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!ELEMENT ProtocolBrand (PackagedContent*) >
  <!ATTLIST ProtocolBrand
   ProtocolId         CDATA   #REQUIRED
   ProtocolBrandId    CDATA   #REQUIRED >

  <!ELEMENT ProtocolAmount (PackagedContent*) >
  <!ATTLIST ProtocolAmount
   ID                 ID      #REQUIRED
   PayProtocolRef     IDREF   #REQUIRED
   CurrencyAmountRefs IDREFS  #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!ELEMENT CurrencyAmount EMPTY >
  <!ATTLIST CurrencyAmount
   ID                 ID      #REQUIRED
   Amount             CDATA   #REQUIRED



Burdett                      Informational                    [Page 268]

RFC 2801                       IOTP/1.0                       April 2000


   CurrCodeType       NMTOKEN 'ISO4217-A'
   CurrCode           CDATA   #REQUIRED >

  <!ELEMENT PayProtocol (PackagedContent*) >
  <!ATTLIST PayProtocol
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #IMPLIED
   ProtocolId         NMTOKEN #REQUIRED
   ProtocolName       CDATA   #REQUIRED
   ActionOrgRef       NMTOKEN #REQUIRED
   PayReqNetLocn      CDATA   #IMPLIED
   SecPayReqNetLocn   CDATA   #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- BRAND SELECTION COMPONENT -->
  <!ELEMENT BrandSelection (BrandSelBrandInfo?,
       BrandSelProtocolAmountInfo?,
       BrandSelCurrencyAmountInfo?) >
  <!ATTLIST BrandSelection
   ID                 ID      #REQUIRED
   BrandListRef       NMTOKEN #REQUIRED
   BrandRef           NMTOKEN #REQUIRED
   ProtocolAmountRef  NMTOKEN #REQUIRED
   CurrencyAmountRef  NMTOKEN #REQUIRED >

  <!ELEMENT BrandSelBrandInfo (PackagedContent+) >
  <!ATTLIST BrandSelBrandInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!ELEMENT BrandSelProtocolAmountInfo (PackagedContent+) >
  <!ATTLIST BrandSelProtocolAmountInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!ELEMENT BrandSelCurrencyAmountInfo (PackagedContent+) >
  <!ATTLIST BrandSelCurrencyAmountInfo
   ID                 ID      #REQUIRED
   ContentSoftwareId  CDATA   #IMPLIED >

  <!-- PAYMENT COMPONENT -->
  <!ELEMENT Payment EMPTY >
  <!ATTLIST Payment
   ID                 ID      #REQUIRED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   BrandListRef       NMTOKEN #REQUIRED



Burdett                      Informational                    [Page 269]

RFC 2801                       IOTP/1.0                       April 2000


   SignedPayReceipt (True | False) #REQUIRED
   StartAfterRefs     NMTOKENS #IMPLIED >


  <!-- PAYMENT SCHEME COMPONENT -->
  <!ELEMENT PaySchemeData (PackagedContent+) >
  <!ATTLIST PaySchemeData
   ID                 ID      #REQUIRED
   PaymentRef         NMTOKEN #IMPLIED
   ConsumerPaymentId  CDATA   #IMPLIED
   PaymentHandlerPayId CDATA  #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- PAYMENT RECEIPT COMPONENT -->
  <!ELEMENT PayReceipt (PackagedContent*) >
  <!ATTLIST PayReceipt
   ID                 ID      #REQUIRED
   PaymentRef         NMTOKEN #REQUIRED
   PayReceiptNameRefs NMTOKENS #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- PAYMENT NOTE COMPONENT -->
  <!ELEMENT PaymentNote (PackagedContent+) >
  <!ATTLIST PaymentNote
    ID                ID      #REQUIRED
    ContentSoftwareId CDATA   #IMPLIED >


  <!-- DELIVERY COMPONENT -->
  <!ELEMENT Delivery (DeliveryData?, PackagedContent*) >
  <!ATTLIST Delivery
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   DelivExch          (True | False) #REQUIRED
   DelivAndPayResp    (True | False) #REQUIRED
   ActionOrgRef       NMTOKEN #IMPLIED >

  <!ELEMENT DeliveryData (PackagedContent*) >
  <!ATTLIST DeliveryData
   xml:lang           NMTOKEN #IMPLIED
   OkFrom             CDATA   #REQUIRED
   OkTo               CDATA   #REQUIRED
   DelivMethod        NMTOKEN #REQUIRED
   DelivToRef         NMTOKEN #REQUIRED
   DelivReqNetLocn    CDATA   #IMPLIED
   SecDelivReqNetLocn CDATA   #IMPLIED



Burdett                      Informational                    [Page 270]

RFC 2801                       IOTP/1.0                       April 2000


   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- CONSUMER DELIVERY DATA COMPONENT -->
  <!ELEMENT ConsumerDeliveryData EMPTY >
  <!ATTLIST ConsumerDeliveryData
   ID                 ID      #REQUIRED
   ConsumerDeliveryId CDATA   #REQUIRED >


  <!-- DELIVERY NOTE COMPONENT -->
  <!ELEMENT DeliveryNote (PackagedContent+) >
  <!ATTLIST DeliveryNote
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   DelivHandlerDelivId CDATA  #IMPLIED
   ContentSoftwareId  CDATA   #IMPLIED >


  <!-- STATUS COMPONENT -->
  <!ELEMENT Status EMPTY >
  <!ATTLIST Status
   ID                 ID      #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   StatusType         NMTOKEN #REQUIRED
   ElRef              NMTOKEN #IMPLIED
   ProcessState (NotYetStarted | InProgress |
       CompletedOk | Failed | ProcessError) #REQUIRED
   CompletionCode     NMTOKEN #IMPLIED
   ProcessReference   CDATA   #IMPLIED
   StatusDesc         CDATA   #IMPLIED >

  <!-- TRADING ROLE DATA COMPONENT -->
  <!ELEMENT TradingRoleData (PackagedContent+) >
  <!ATTLIST TradingRoleData
    ID                ID      #REQUIRED
    OriginatorElRef   NMTOKEN #REQUIRED
    DestinationElRefs NMTOKENS #REQUIRED >

  <!-- INQUIRY TYPE COMPONENT -->
  <!ELEMENT InquiryType EMPTY >
  <!ATTLIST InquiryType
   ID                 ID      #REQUIRED
   Type               NMTOKEN #REQUIRED
   ElRef              NMTOKEN #IMPLIED
   ProcessReference   CDATA   #IMPLIED >





Burdett                      Informational                    [Page 271]

RFC 2801                       IOTP/1.0                       April 2000


  <!-- ERROR COMPONENT -->
  <!ELEMENT ErrorComp (ErrorLocation+, PackagedContent*) >
  <!ATTLIST ErrorComp
   ID                 NMTOKEN #REQUIRED
   xml:lang           NMTOKEN #REQUIRED
   ErrorCode          NMTOKEN #REQUIRED
   ErrorDesc          CDATA   #REQUIRED
   Severity (Warning|TransientError|HardError) #REQUIRED
   MinRetrySecs       CDATA   #IMPLIED
   SwVendorErrorRef   CDATA   #IMPLIED >


  <!ELEMENT ErrorLocation EMPTY >
  <!ATTLIST ErrorLocation
   ElementType        NMTOKEN #REQUIRED
   IotpMsgRef         NMTOKEN #IMPLIED
   BlkRef             NMTOKEN #IMPLIED
   CompRef            NMTOKEN #IMPLIED
   ElementRef         NMTOKEN #IMPLIED
   AttName            NMTOKEN #IMPLIED >



  <!--
  ******************************************************
  * TRADING BLOCKS                                     *
  ******************************************************
   -->

  <!-- TRADING PROTOCOL OPTIONS BLOCK -->
  <!ELEMENT TpoBlk ( ProtocolOptions, BrandList*, Org* ) >
  <!ATTLIST TpoBlk
   ID                 ID      #REQUIRED >


  <!-- TPO SELECTION BLOCK -->
  <!ELEMENT TpoSelectionBlk (BrandSelection+) >
  <!ATTLIST TpoSelectionBlk
   ID                 ID      #REQUIRED >


  <!-- OFFER RESPONSE BLOCK -->
  <!ELEMENT OfferRespBlk (Status, Order?, Payment*,
               Delivery?, TradingRoleData*) >
  <!ATTLIST OfferRespBlk
   ID                 ID      #REQUIRED >





Burdett                      Informational                    [Page 272]

RFC 2801                       IOTP/1.0                       April 2000


  <!-- AUTHENTICATION REQUEST BLOCK -->
  <!ELEMENT AuthReqBlk (AuthReq*, TradingRoleInfoReq?) >
  <!ATTLIST AuthReqBlk
   ID                 ID      #REQUIRED >


  <!-- AUTHENTICATION RESPONSE BLOCK -->
  <!ELEMENT AuthRespBlk (AuthResp?, Org*) >
  <!ATTLIST AuthRespBlk
   ID                 ID      #REQUIRED >


  <!-- AUTHENTICATION STATUS BLOCK -->
  <!ELEMENT AuthStatusBlk (Status) >
  <!ATTLIST AuthStatusBlk
   ID                 ID      #REQUIRED >


  <!-- PAYMENT REQUEST BLOCK -->
  <!ELEMENT PayReqBlk (Status+, BrandList, BrandSelection,
       Payment, PaySchemeData?, Org*, TradingRoleData*) >
  <!ATTLIST PayReqBlk
   ID                 ID      #REQUIRED >


  <!-- PAYMENT EXCHANGE BLOCK -->
  <!ELEMENT PayExchBlk (PaySchemeData) >
  <!ATTLIST PayExchBlk
   ID                 ID      #REQUIRED >


  <!-- PAYMENT RESPONSE BLOCK -->
  <!ELEMENT PayRespBlk (Status, PayReceipt?, PaySchemeData?,
       PaymentNote?, TradingRoleData*) >
  <!ATTLIST PayRespBlk
   ID                 ID      #REQUIRED >
  <!-- DELIVERY REQUEST BLOCK -->
  <!ELEMENT DeliveryReqBlk (Status+, Order, Org*, Delivery,
       ConsumerDeliveryData?, TradingRoleData*) >
  <!ATTLIST DeliveryReqBlk
   ID                 ID      #REQUIRED >


  <!-- DELIVERY RESPONSE BLOCK -->
  <!ELEMENT DeliveryRespBlk (Status, DeliveryNote) >
  <!ATTLIST DeliveryRespBlk
   ID                 ID      #REQUIRED >




Burdett                      Informational                    [Page 273]

RFC 2801                       IOTP/1.0                       April 2000


  <!-- INQUIRY REQUEST BLOCK -->
  <!ELEMENT InquiryReqBlk ( InquiryType, PaySchemeData? ) >
  <!ATTLIST InquiryReqBlk
   ID                 ID      #REQUIRED >


  <!-- INQUIRY RESPONSE BLOCK -->
  <!ELEMENT InquiryRespBlk (Status, PaySchemeData?) >
  <!ATTLIST InquiryRespBlk
   ID                 ID      #REQUIRED
   LastReceivedIotpMsgRef NMTOKEN #IMPLIED
   LastSentIotpMsgRef NMTOKEN #IMPLIED >


  <!-- PING REQUEST BLOCK -->
  <!ELEMENT PingReqBlk (Org*)>
  <!ATTLIST PingReqBlk
   ID                 ID      #REQUIRED>


  <!-- PING RESPONSE BLOCK -->
  <!ELEMENT PingRespBlk (Org+)>
  <!ATTLIST PingRespBlk
   ID                 ID      #REQUIRED
   PingStatusCode (Ok | Busy | Down) #REQUIRED
   SigVerifyStatusCode (Ok | NotSupported | Fail) #IMPLIED
   xml:lang           NMTOKEN #IMPLIED
   PingStatusDesc     CDATA   #IMPLIED>


  <!-- ERROR BLOCK -->
  <!ELEMENT ErrorBlk (ErrorComp+, PaySchemeData*) >
  <!ATTLIST ErrorBlk
   ID                 ID      #REQUIRED >


  <!-- CANCEL BLOCK -->
  <!ELEMENT CancelBlk (Status) >
  <!ATTLIST CancelBlk
   ID                 ID      #REQUIRED >


  <!--
  ******************************************************
  * IOTP SIGNATURES BLOCK DEFINITION                   *
  ******************************************************
  -->




Burdett                      Informational                    [Page 274]

RFC 2801                       IOTP/1.0                       April 2000


  <!ELEMENT IotpSignatures (Signature+ ,Certificate*) >
  <!ATTLIST IotpSignatures
      ID        ID        #IMPLIED
  >

  <!--
  ******************************************************
  * IOTP SIGNATURE COMPONENT DEFINITION                *
  ******************************************************
  -->

  <!ELEMENT Signature (Manifest, Value+) >
  <!ATTLIST Signature
      ID         ID        #IMPLIED
  >

  <!ELEMENT Manifest
      (       Algorithm+,
              Digest+,
              Attribute*,
              OriginatorInfo,
              RecipientInfo+
      )
  >

  <!ATTLIST Manifest
      LocatorHRefBase       CDATA             #IMPLIED
  >

  <!ELEMENT Algorithm (Parameter*) >
  <!ATTLIST Algorithm
      ID                     ID                #REQUIRED
      type            (digest|signature)      #IMPLIED
      name                  NMTOKEN           #REQUIRED
  >

  <!ELEMENT Digest (Locator, Value) >
  <!ATTLIST Digest
      DigestAlgorithmRef    IDREF             #REQUIRED
  >

  <!ELEMENT Attribute ( ANY ) >
  <!ATTLIST Attribute
      type                   NMTOKEN           #REQUIRED
      critical            ( true | false )     #REQUIRED
  >

  <!ELEMENT OriginatorInfo ANY >



Burdett                      Informational                    [Page 275]

RFC 2801                       IOTP/1.0                       April 2000


  <!ATTLIST OriginatorInfo
      OriginatorRef           NMTOKEN          #IMPLIED
  >

  <!ELEMENT RecipientInfo ANY >
  <!ATTLIST RecipientInfo
      SignatureAlgorithmRef   IDREF            #REQUIRED
      SignatureValueRef       IDREF            #IMPLIED
      SignatureCertRef        IDREF            #IMPLIED
      RecipientRefs           NMTOKENS         #IMPLIED
  >

  <!ELEMENT KeyIdentifier EMPTY>
  <!ATTLIST KeyIdentifier
      value                    CDATA           #REQUIRED
  >

  <!ELEMENT Parameter ANY >
  <!ATTLIST Parameter
      type                     CDATA           #REQUIRED
  >


  <!--
  ******************************************************
  * IOTP CERTIFICATE COMPONENT DEFINITION              *
  ******************************************************
  -->

  <!ELEMENT Certificate
   (  IssuerAndSerialNumber,  ( Value | Locator ) )
  >

  <!ATTLIST Certificate
      ID                        ID                #IMPLIED
      type                      NMTOKEN           #REQUIRED
  >

  <!ELEMENT IssuerAndSerialNumber EMPTY >
  <!ATTLIST IssuerAndSerialNumber
      issuer                     CDATA            #REQUIRED
      number                     CDATA            #REQUIRED
  >

  <!--
  ******************************************************
  * IOTP SHARED COMPONENT DEFINITION                   *
  ******************************************************



Burdett                      Informational                    [Page 276]

RFC 2801                       IOTP/1.0                       April 2000


  -->
  <!ELEMENT Value ( #PCDATA ) >
  <!ATTLIST Value
      ID               ID           #IMPLIED
      encoding    (base64|none)    'base64'
  >

  <!ELEMENT Locator EMPTY>
  <!ATTLIST Locator
      xml:link        CDATA         #FIXED        'simple'
      href            CDATA         #REQUIRED
  >

14. Glossary

  This section contains a glossary of some of the terms used within
  this specification in alphabetical order.

         NAME                            DESCRIPTION

  Authenticator      The Organisation which is requesting the
                     authentication of another Organisation, and

  Authenticatee      The Organisation being authenticated by an
                     Authenticator

  Business Error     See Status Component.

  Brand              A Brand is the mark which identifies a particular
                     type of Payment Instrument. A list of Brands are
                     the payment options which are presented by the
                     Merchant to the Consumer and from which the
                     Consumer makes a selection. Each Brand may have a
                     different Payment Handler. Examples of Brands
                     include:
                      o payment association and proprietary Brands,
                        for example MasterCard, Visa, American Express,
                        Diners Club, American Express, Mondex,
                        GeldKarte, CyberCash, etc.
                      o Promotional Brands (see below). These include:
                      o store Brands, where the Payment Instrument is
                        issued to a Consumer by a particular Merchant,
                        for example Walmart, Sears, or Marks and
                        Spencer (UK)
                      o coBrands, for example American Advantage Visa,
                        where an a company uses their own Brand in
                        conjunction with, typically, a payment
                        association Brand.



Burdett                      Informational                    [Page 277]

RFC 2801                       IOTP/1.0                       April 2000


  Consumer           The Organisation which is to receive the benefit
                     of and typically pay for the goods or services.

  ContentSoftwareId  This contains information which identifies the
                     software which generated the content of the
                     element. Its purpose is to help resolve
                     interoperability problems that might occur as a
                     result of incompatibilities between messages
                     produced by different software. It is a single
                     text string in the language defined by xml:lang.
                     It must contain, as a minimum:
                      o the name of the software manufacturer
                      o the name of the software
                      o the version of the software, and
                      o the build of the software

                     It is recommended that this attribute is included
                     whenever the software which generated the content
                     cannot be identified from the SoftwareId attribute
                     on the Message Id Component (see section 3.3.2)

  Customer Care      An Organisation that is providing customer care
  Provider           typically on behalf of a Merchant. Examples of
                     customer care include, responding to problems
                     raised by a Consumer arising from an IOTP
                     Transaction that the Consumer took part in.

  Delivery Handler   The Organisation that directly delivers the goods
                     or services to the Consumer on behalf of the
                     Merchant. Delivery can be in the form of either
                     digital goods (e.g., a [MIME] message), or
                     physically delivered using the post or a courier.

  Document Exchange  A Document Exchange consists of a set of IOTP
                     Messages exchanged between two parties that
                     implement part or all of two Trading Exchanges
                     simultaneously in order to minimise the number of
                     actual IOTP Messages which must be sent over the
                     Internet.

                     Document Exchanges are combined together in
                     sequence to implement a particular IOTP
                     Transaction.

  Dual Brand         A Dual Brand means that a single Payment
                     Instrument may be used as if it were two separate
                     Brands. For example there could be a single
                     Japanese "UC" MasterCard which can be used as



Burdett                      Informational                    [Page 278]

RFC 2801                       IOTP/1.0                       April 2000


                     either a UC card or a regular MasterCard. The UC
                     card Brand and the MasterCard Brand could each
                     have their own separate Payment Handlers. This
                     means that:
                      o the Merchant treats, for example "UC" and
                        "MasterCard" as two separate Brands when
                        offering a list of Brands to the Consumer,
                      o the Consumer chooses a Brand, for example
                        either "UC" or "MasterCard,
                      o the Consumer IOTP aware application determines
                        which Payment Instrument(s) match the chosen
                        Brand, and selects, perhaps with user
                        assistance, the correct Payment Instrument to
                        use.

  Error Block        An Error Block reports that a Technical Error was
                     found in an IOTP Message that was previously
                     received. Typically Technical Errors are caused by
                     errors in the XML which has been received or some
                     technical failure of the processing of the IOTP
                     Message. Frequently the generation or receipt of
                     an Error Block will result in failure of the IOTP
                     Transaction. They are distinct from Business
                     Errors, reported in a Status Component, which can
                     also cause failure of an IOTP Transaction.

  Exchange Block     An Exchange Block is sent between the two Trading
                     Roles involved in a Trading Exchange. It contains
                     one or more Trading Components. Exchange Blocks
                     are always sent after a Request Block and before a
                     Response Block in a Trading Exchange. The content
                     of an Exchange Block is dependent on the type of
                     Trading Exchange being carried out.

  IOTP Message       An IOTP Message is the outermost wrapper for the
                     document(s) which are sent between Trading Roles
                     that are taking part in a trade. It is a well
                     formed XML document. The documents it contains
                     consist of:
                      o a Transaction Reference Block to uniquely
                        identify the IOTP Transaction of which the IOTP
                        Message is part,
                      o an optional Signature Block to digitally sign
                        the Trading Blocks or Trading Components
                        associated with the IOTP Transaction
                      o an optional Error Block to report on technical
                        errors contained in a previously received IOTP
                        Message, and



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RFC 2801                       IOTP/1.0                       April 2000


                      o a collection of IOTP Trading Blocks which
                        carries the data required to carry out an IOTP
                        Transaction.

  IOTP Transaction   An instance of an Internet Open Trading Protocol
                     Transaction consists of a set of IOTP Messages
                     transferred between Trading Roles. The rules for
                     what may be contained in the IOTP Messages is
                     defined by the Transaction Type of the IOTP
                     Transaction.

  IOTP Transaction   A Transaction Type identifies the type an of IOTP
  Type               Transaction. Examples of Transaction Type include:
                     Purchase, Refund, Authentication, Withdrawal,
                     Deposit (of electronic cash). The Transaction Type
                     specifies for an IOTP Transaction:
                      o the Trading Exchanges which may be included in
                        the transaction,
                      o how those Trading Exchanges may be combined to
                        meet the business needs of the transaction
                      o which Trading Blocks may be included in the
                        IOTP Messages that make up the transaction
                      o Consult this specification for the rules that
                        apply for each Transaction Type.

  Merchant           The Organisation from whom the service or goods
                     are being obtained, who is legally responsible for
                     providing the goods or services and receives the
                     benefit of any payment made

  Merchant Customer  The Organisation that is involved with customer
  Care Provider      dispute negotiation and resolution on behalf of
                     the Merchant

  Organisation       A company or individual that takes part in a Trade
                     as a Trading Role. The Organisations may take one
                     or more of the roles involved in the Trade

  Payment Handler    The Organisation that physically receives the
                     payment from the Consumer on behalf of the
                     Merchant

  Payment            A Payment Instrument is the means by which
  Instrument         Consumer pays for goods or services offered by a
                     Merchant. It can be, for example:
                      o a credit card such as MasterCard or Visa;
                      o a debit card such as MasterCard's Maestro;
                      o a smart card based electronic cash Payment



Burdett                      Informational                    [Page 280]

RFC 2801                       IOTP/1.0                       April 2000


                        Instrument such as a Mondex Card, a GeldKarte
                        card or a Visa Cash card
                      o a software based electronic payment account
                        such as a CyberCash's CyberCoin or DigiCash
                        account.

                     All Payment Instruments have a number, typically
                     an account number, by which the Payment Instrument
                     can be identified.

  Promotional Brand  A Promotional Brand means that, if the Consumer
                     pays with that Brand, then the Consumer will
                     receive some additional benefit which can be
                     received in two ways:
                      o at the time of purchase. For example if a
                        Consumer pays with a "Walmart MasterCard" at a
                        Walmart web site, then a 5% discount might
                        apply, which means the Consumer actually pays
                        less,
                      o from their Payment Instrument (card) issuer
                        when the payment appears on their statement.
                        For example loyalty points in a frequent flyer
                        scheme could be awarded based on the total
                        payments made with the Payment Instrument since
                        the last statement was issued.

                     Each Promotional Brand should be identified as a
                     separate Brand in the list of Brands offered by
                     the Merchant.

  Receipt Component  A Receipt Component is a record of the successful
                     completion of a Trading Exchange. Examples of
                     Receipt Components include: Payment Receipts, and
                     Delivery Notes. It's content may dependent on the
                     technology used to perform the Trading Exchange.
                     For example a Secure Electronic Transaction (SET)
                     payment receipt consists of SET payment messages
                     which record the result of the payment.

  Request Block      A Request Block is Trading Block that contains a
                     request for a Trading Exchange to start. The
                     Trading Components in a Request Block may be
                     signed by a Signature Block so that their
                     authenticity may be checked and to determine that
                     the Trading Exchange being requested is
                     authorised. Authorisation for a Trading Exchange
                     to start can be provided by the signatures
                     contained on Receipt Components contained in



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RFC 2801                       IOTP/1.0                       April 2000


                     Response Blocks resulting from previously
                     completed Trading Exchanges.  Examples of Request
                     Blocks are Payment Request and Delivery Request

  Response Block     A Response Block is a Trading Block that indicates
                     that a Trading Exchange is complete. It is sent by
                     the Trading Role that received a Request Block to
                     the Trading Role that sent the Request Block. The
                     Response Block contains a Status Component that
                     contains information about the completion of the
                     Trading Exchange, for example it indicates whether
                     or not the Trading Exchange completed
                     successfully. For some Trading Exchanges the
                     Response Block contains a Receipt Component that
                     forms a record of the Trading Exchange. Receipt
                     Components may be digitally signed using a
                     Signature Block to make completion non-refutable.
                     Examples of Response Blocks include Offer
                     Response, Payment Response and Delivery Response.

  Signature Block    A Signature Block is a Trading Block that contains
                     one or more digital signatures in the form of
                     Signature Components. A Signature Component may
                     digitally sign any Block or Component in any IOTP
                     Message in the same IOTP Transaction.

  Status Component   A Status Component contains information that
                     describes the state of a Trading Exchange.

                     Before the Trading Exchange is complete the Status
                     Component can indicate information about how the
                     Trading Exchange is progressing.

                     Once a Trading Exchange is complete the Status
                     Component can only indicate the success of the
                     Trading Exchange or that a Business Error has
                     occurred.

                     A Business Error indicates that continuation with
                     the Trading Exchange was not possible because of
                     some business rule or logic, for example,
                     "insufficient funds available", rather than any
                     Technical Error associated with the content or
                     format of the IOTP Messages in the IOTP
                     Transaction.

  Technical Error    See Error Block.




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RFC 2801                       IOTP/1.0                       April 2000


  Trading Block      A Trading Block consists of one or more Trading
                     Components. One or more Trading Blocks may be
                     contained within the IOTP Messages which are
                     physically sent in the form of [XML] documents
                     between the different Trading Roles that are
                     taking part in a trade. Trading Blocks are of
                     three main types:
                      o a Request Block,
                      o an Exchange Block, or a
                      o a Response Block

  Trading Component  A Trading Component is a collection of XML
                     elements and attributes. Trading Components are
                     the child elements of the Trading Blocks. Examples
                     of Trading Components are: Offer, Brand List,
                     Payment Receipt, Delivery [information], Payment
                     Amount [information]

  Trading Exchange   A Trading Exchange consists of the exchange,
                     between two Trading Roles, of a sequence of
                     documents. The documents may be in the form of
                     Trading Blocks or they may be transferred by some
                     other means, for example through entering data
                     into a web page. Each Trading Exchange consists of
                     three main parts:
                      o the sending of a Request Block by one Trading
                        Role (the initiator) to another Trading Role
                        (the recipient),
                      o the optional exchange of one or more Exchange
                        Blocks between the recipient and the initiator,
                        until eventually,
                      o the Trading Role that received the Request
                        Block sends a Response Block to the initiator.

                     A Trading Exchange is designed to implement a
                     useful service of some kind. Examples of Trading
                     Exchanges/services are:
                      o Offer, which results in a Consumer receiving
                        an offer from a Merchant to carry out a
                        business transaction of some kind,
                      o Payment, where a Consumer makes a payment to a
                        Payment Handler,
                      o Delivery, where a Consumer requests, and
                        optionally obtains, delivery of goods or
                        services from a Delivery Handler, and
                      o Authentication, where any Trading Role may
                        request and receive information about another
                        Trading Role.



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RFC 2801                       IOTP/1.0                       April 2000


  Trading Role       A Trading Role identifies the different ways in
                     which Organisations can participate in a trade.
                     There are five Trading Roles: Consumer, Merchant,
                     Payment Handler, Delivery Handler, and Merchant
                     Customer Care Provider.

  Transaction        A Transaction Reference Block identifies an IOTP
  Reference Block    Transaction. It contains data that identifies:
                      o the Transaction Type,
                      o the IOTP Transaction uniquely, through a
                        globally unique transaction identifier
                      o the IOTP Message uniquely within the IOTP
                        Transaction, through a message identifier

                     The Transaction Reference Block may also contain
                     references to other transactions which may or may
                     not be IOTP Transactions

15. References

  This section contains references to related documents identified in
  this specification.

  [Base64]    Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part One: Format of Internet Message
              Bodies", RFC 2045, November 1996.

  [DOM-HASH]  Maruyama, H., Tamura, K. and N. Uramoto, "Digest Values
              for DOM (DOMHASH)", RFC 2803, April 2000.

  [DNS]       Mockapetris, P., "Domain names - concepts and
              facilities", STD 13, RFC 1034, November 1987.

  [DNS]       Mockapetris, P., "Domain names - implementation and
              specification", STD 13, RFC 1035, November 1987.

  [DSA]       The Digital Signature Algorithm (DSA) published by the
              National Institute of Standards and Technology (NIST) in
              the Digital Signature Standard (DSS), which is a part of
              the US government's Capstone project.

  [ECCDSA]    Elliptic Curve Cryptosystems Digital Signature Algorithm
              (ECCDSA). Elliptic curve cryptosystems are analogues of
              public-key cryptosystems such as RSA in which modular
              multiplication is replaced by the elliptic curve addition
              operation. See: V. S. Miller. Use of elliptic curves in
              cryptography. In Advances in Cryptology - Crypto '85,
              pages 417-426, Springer-Verlag, 1986.



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RFC 2801                       IOTP/1.0                       April 2000


  [HMAC]      Krawczyk, H., Bellare, M. and R. Canetti, "HMAC:  Keyed-
              Hashing for Message Authentication", RFC 2104, February
              1997.

  [HTML]      Berners-Lee, T. and D. Connolly, "Hypertext Markup
              Language - 2.0", RFC 1866, November 1995.

  [HTML]      Hyper Text Mark Up Language. The Hypertext Mark-up
              Language (HTML) is a simple mark-up language used to
              create hypertext documents that are platform independent.
              See the World Wide Web (W3C) consortium web site at:
              http://www.w3.org/MarkUp/

  [HTTP]      Berners-Lee, T., Fielding, R. and H. Frystyk, "Hypertext
              Transfer Protocol -- HTTP/1.0", RFC 1945, May 1996.

  [HTTP]      Fielding, R., Gettys, J., Mogul, J., Frystyk, T. and T.
              Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1.",
              RFC 2616, June 1999.

  [IANA]      The Internet Assigned Numbers Authority. The organisation
              responsible for co-ordinating the names and numbers
              associated with the Internet. See http://www.iana.org/

  [ISO4217]   ISO 4217: Codes for the Representation of Currencies.
              Available from ANSI or ISO.

  [IOTPDSIG]  Davidson, K. and Y. Kawatsura, "Digital Signatures for
              the v1.0 Internet Open Trading Protocol (IOTP)", RFC
              2802, April 2000.

  [MD5]       Rivest, R., "The MD5 Message-Digest Algorithm", RFC 1321,
              April 1992.

  [MIME]      Crocker, D., "Standard for the Format of ARPA Internet
              Text Messages", STD 11, RFC 822, August 1982.

  [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part One: Format of Internet Message
              Bodies", RFC 2045, November 1996.

  [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part Two: Media Types", RFC 2046,
              November 1996.

  [MIME]      Moore, K., "MIME (Multipurpose Internet Mail Extensions)
              Part Three: Message Header Extensions for Non-ASCII Text"
              RFC 2047, November 1996.



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RFC 2801                       IOTP/1.0                       April 2000


  [MIME]      Freed, N., Klensin, J. and J. Postel, "Multipurpose
              Internet Mail Extensions (MIME) Part Four: Registration
              Procedures", RFC 2048, November 1996.

  [MIME]      Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part Five: Conformance Criteria and
              Examples" RFC 2049, November 1996.

  [OPS]       Open Profiling Standard. A proposed standard which
              provides a framework with built-in privacy safeguards for
              the trusted exchange of profile information between
              individuals and web sites.  Being developed by Netscape
              and Microsoft amongst others.

  [RFC1738]   Berners-Lee, T., Masinter, L. and M. McCahill, "Uniform
              Resource Locators (URL)", RFC 1738, December 1994.

  [RFC2434]   Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 2434,
              October 1998.

  [RSA]       RSA is a public-key cryptosystem for both encryption and
              authentication supported by RSA Data Security Inc. See:
              R. L. Rivest, A. Shamir, and L.M. Adleman. A method for
              obtaining digital signatures and public-key
              cryptosystems. Communications of the ACM, 21(2): 120-126,
              February 1978.

  [SCCD]      Secure Channel Credit Debit. A method of conducting a
              credit or debit card payment where unauthorised access to
              account information is prevented through use of secure
              channel transport mechanisms such as SSL/TLS. An IOTP
              supplement describing how SCCD works is under
              development.

  [SET]       Secure Electronic Transaction Specification, Version 1.0,
              May 31, 1997. Supports credit and debit card payments
              using certificates at the Consumer and Merchant to help
              ensure authenticity.  Download from:
              <http://www.setco.org>.

  [SSL/TLS]   Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
              RFC 2246, January 1999.

  [SHA1]      [FIPS-180-1]"Secure Hash Standard", National Institute of
              Standards and Technology, US Department Of Commerce,
              April 1995. Also known as: 59 Fed Reg. 35317 (1994). See
              http://www.itl.nist.gov/div897/pubs/fip180-1.htm



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RFC 2801                       IOTP/1.0                       April 2000


  [UTC]       Universal Time Co-ordinated. A method of defining time
              absolutely relative to Greenwich Mean Time (GMT).
              Typically of the form:  "CCYY-MM-DDTHH:MM:SS.sssZ+n"
              where the "+n" defines the number of hours from GMT. See
              ISO DIS8601.

  [UTF16]     The Unicode Standard, Version 2.0.  The Unicode
              Consortium, Reading, Massachusetts. See ISO/IEC 10646 1
              Proposed Draft Amendment 1

  [X.509]     ITU Recommendation X.509 1993 | ISO/IEC 9594-8: 1995,
              Including Draft Amendment 1: Certificate Extensions
              (Version 3 Certificate)

  [XML        Recommendation for Namespaces in XML, World Wide Web
  Namespace]  Consortium, 14 January 1999, "http://www.w3.org/TR/REC-
              xml-names"

  [XML]       Extensible Mark Up Language. A W3C recommendation. See
              http://www.w3.org/TR/1998/REC-xml-19980210 for the 10
              February 1998 version.

16. Author's Address

  The author of this document is:

  David Burdett
  Commerce One
  4440 Rosewood Drive, Bldg 4
  Pleasanton
  California 94588
  USA

  Phone: +1 (925) 520 4422
  EMail: [email protected]

  The author of this document particularly wants to thank Mondex
  International Limited (www.mondex.com) for the tremendous support
  provided in the formative stages of the development of this
  specification.











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  In addition the author appreciates the following contributors to this
  protocol (in alphabetic order of company) without which it could not
  have been developed.

     -  Phillip Mullarkey, British Telecom plc

     -  Andrew Marchewka, Canadian Imperial Bank of Commerce

     -  Brian Boesch, CyberCash Inc.

     -  Tom Arnold, CyberSource

     -  Terry Allen, Commerce One (formally Veo Systems)

     -  Richard Brown, GlobeSet Inc.

     -  Peter Chang, Hewlett Packard

     -  Masaaki Hiroya, Hitachi Ltd

     -  Yoshiaki Kawatsura, Hitachi Ltd

     -  Mark Linehan, International Business Machines

     -  Jonathan Sowler, JCP Computer Services Ltd

     -  John Wankmueller, MasterCard International

     -  Steve Fabes, Mondex International Ltd

     -  Donald Eastlake 3rd, Motorola Inc (formerly International
        Business Machines Inc)

     -  Surendra Reddy, Oracle Corporation

     -  Akihiro Nakano, Plat Home, Inc. (ex Hitachi Ltd)

     -  Chris Smith, Royal Bank of Canada

     -  Hans Bernhard-Beykirch, SIZ (IT Development and Coordination

        Centre of the German Savings Banks Organisation)

     -  W. Reid Carlisle, Spyrus (ex Citibank Universal Card Services,
        formally AT&T Universal Card Services)

     -  Efrem Lipkin, Sun Microsystems




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     -  Tony Lewis, Visa International

  The author would also like to thank the following organisations for
  their support:

     -  Amino Communications

     -  DigiCash

     -  Fujitsu

     -  General Information Systems

     -  Globe Id Software

     -  Hyperion

     -  InterTrader

     -  Nobil I T Corp

     -  Mercantec

     -  Netscape

     -  Nippon Telegraph and Telephone Corporation

     -  Oracle Corporation

     -  Smart Card Integrations Ltd.

     -  Spyrus

     -  Verifone

     -  Unisource nv

     -  Wells Fargo Bank













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RFC 2801                       IOTP/1.0                       April 2000


17. Full Copyright Statement

  Copyright (C) The Internet Society (2000).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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