Network Working Group                                      S. Hollenbeck
Request for Comments: 3730                                VeriSign, Inc.
Category: Standards Track                                     March 2004


                Extensible Provisioning Protocol (EPP)

Status of this Memo

  This document specifies an Internet standards track protocol for the
  Internet community, and requests discussion and suggestions for
  improvements.  Please refer to the current edition of the "Internet
  Official Protocol Standards" (STD 1) for the standardization state
  and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2004).  All Rights Reserved.

Abstract

  This document describes an application layer client-server protocol
  for the provisioning and management of objects stored in a shared
  central repository.  Specified in XML, the protocol defines generic
  object management operations and an extensible framework that maps
  protocol operations to objects.  This document includes a protocol
  specification, an object mapping template, and an XML media type
  registration.

Table of Contents

  1.  Introduction. . . . . . . . . . . . . . . . . . . . . . . . .   2
      1.1.  Conventions Used in This Document . . . . . . . . . . .   3
  2.  Protocol Description. . . . . . . . . . . . . . . . . . . . .   3
      2.1.  Transport Mapping Considerations. . . . . . . . . . . .   6
      2.2.  Protocol Identification . . . . . . . . . . . . . . . .   7
      2.3.  Hello Format. . . . . . . . . . . . . . . . . . . . . .   7
      2.4.  Greeting Format . . . . . . . . . . . . . . . . . . . .   8
      2.5.  Command Format. . . . . . . . . . . . . . . . . . . . .  11
      2.6.  Response Format . . . . . . . . . . . . . . . . . . . .  12
      2.7.  Protocol Extension Framework. . . . . . . . . . . . . .  16
            2.7.1.  Protocol Extension. . . . . . . . . . . . . . .  16
            2.7.2.  Object Extension. . . . . . . . . . . . . . . .  17
            2.7.3.  Command-Response Extension. . . . . . . . . . .  18
      2.8.  Object Identification . . . . . . . . . . . . . . . . .  19
      2.9.  Protocol Commands . . . . . . . . . . . . . . . . . . .  19
            2.9.1.  Session Management Commands . . . . . . . . . .  20
                    2.9.1.1.  EPP <login> Command . . . . . . . . .  20



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                    2.9.1.2.  EPP <logout> Command. . . . . . . . .  22
            2.9.2.  Query Commands. . . . . . . . . . . . . . . . .  23
                    2.9.2.1.  EPP <check> Command . . . . . . . . .  24
                    2.9.2.2.  EPP <info> Command. . . . . . . . . .  26
                    2.9.2.3.  EPP <poll> Command. . . . . . . . . .  27
                    2.9.2.4.  EPP <transfer> Query Command. . . . .  32
            2.9.3.  Object Transform Commands . . . . . . . . . . .  34
                    2.9.3.1.  EPP <create> Command. . . . . . . . .  34
                    2.9.3.2.  EPP <delete> Command. . . . . . . . .  35
                    2.9.3.3.  EPP <renew> Command . . . . . . . . .  37
                    2.9.3.4.  EPP <transfer> Command. . . . . . . .  38
                    2.9.3.5.  EPP <update> Command. . . . . . . . .  41
  3.  Result Codes. . . . . . . . . . . . . . . . . . . . . . . . .  42
  4.  Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . .  48
      4.1.  Base Schema . . . . . . . . . . . . . . . . . . . . . .  49
      4.2.  Shared Structure Schema . . . . . . . . . . . . . . . .  58
  5.  Internationalization Considerations . . . . . . . . . . . . .  60
  6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  61
  7.  Security Considerations . . . . . . . . . . . . . . . . . . .  62
  8.  Acknowledgements. . . . . . . . . . . . . . . . . . . . . . .  62
  9.  References. . . . . . . . . . . . . . . . . . . . . . . . . .  63
      9.1.  Normative References. . . . . . . . . . . . . . . . . .  63
      9.2.  Informative References. . . . . . . . . . . . . . . . .  64
  Appendix A: Object Mapping Template . . . . . . . . . . . . . . .  65
  Appendix B: Media Type Registration: application/epp+xml. . . . .  67
  Author's Address. . . . . . . . . . . . . . . . . . . . . . . . .  68
  Full Copyright Statement. . . . . . . . . . . . . . . . . . . . .  69

1.  Introduction

  This document describes specifications for the Extensible
  Provisioning Protocol (EPP) version 1.0, an XML text protocol that
  permits multiple service providers to perform object provisioning
  operations using a shared central object repository.  EPP is
  specified using the Extensible Markup Language (XML) 1.0 as described
  in [XML] and XML Schema notation as described in [XMLS-1] and [XMLS-
  2].  EPP meets and exceeds the requirements for a generic registry
  registrar protocol as described in [RFC3375].

  EPP content is identified by MIME media type application/epp+xml.
  Registration information for this media type is included in an
  appendix to this document.

  EPP is intended for use in diverse operating environments where
  transport and security requirements vary greatly.  It is unlikely
  that a single transport or security specification will meet the needs
  of all anticipated operators, so EPP was designed for use in a




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  layered protocol environment.  Bindings to specific transport and
  security protocols are outside the scope of this specification.

  This original motivation for this protocol was to provide a standard
  Internet domain name registration protocol for use between domain
  name registrars and domain name registries.  This protocol provides a
  means of interaction between a registrar's applications and registry
  applications.  It is expected that this protocol will have additional
  uses beyond domain name registration.

  XML is case sensitive.  Unless stated otherwise, XML specifications
  and examples provided in this document MUST be interpreted in the
  character case presented to develop a conforming implementation.

1.1.  Conventions Used In This Document

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
  document are to be interpreted as described in [RFC2119].

  In examples, "C:" represents lines sent by a protocol client and "S:"
  represents lines returned by a protocol server.  Indentation and
  white space in examples is provided only to illustrate element
  relationships and is not a REQUIRED feature of this protocol.

2.  Protocol Description

  EPP is a stateful XML protocol that can be layered over multiple
  transport protocols.  Protected using lower-layer security protocols,
  clients exchange identification, authentication, and option
  information, and then engage in a series of client-initiated
  command-response exchanges.  All EPP commands are atomic (there is no
  partial success or partial failure) and designed so that they can be
  made idempotent (executing a command more than once has the same net
  effect on system state as successfully executing the command once).

  EPP provides four basic service elements: service discovery,
  commands, responses, and an extension framework that supports
  definition of managed objects and the relationship of protocol
  requests and responses to those objects.

  An EPP server MUST respond to client-initiated communication (which
  can be either a lower-layer connection request or an EPP service
  discovery message) by returning a greeting to a client.  A server
  MUST promptly respond to each EPP command with a coordinated response
  that describes the results of processing the command.  The following
  server state machine diagram illustrates the message exchange process
  in detail:



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          |
          V
  +-----------------+                  +-----------------+
  |   Waiting for   |     Connected    |     Prepare     |
  |      Client     |----------------->|     Greeting    |
  +-----------------+    or <hello>    +-----------------+
     ^                                           |
     | Close Connection                     Send |
     |     or Idle                      Greeting |
  +-----------------+                            V
  |       End       |     Timeout      +-----------------+
  |     Session     |<-----------------|   Waiting for   |
  +-----------------+                  |      Client     |
     ^    ^    ^        Send +-------->|  Authentication |
     |    |    |    Response |         +-----------------+
     |    |    |     +--------------+            |
     |    |    |     | Prepare Fail |            | <login>
     |    |    +-----|   Response   |            | Received
     |    |    Send  +--------------+            V
     |    |    2501          ^         +-----------------+
     |    |   Response       |         |   Processing    |
     |    |                  +---------|     <login>     |
     |    |                  Auth Fail +-----------------+
     |    |                                       |
     |    |                                       | Auth OK
     |    |                                       V
     |    |              Timeout       +-----------------+
     |    +----------------------------|   Waiting for   |
     |                                 |     Command     |
     | Send x5xx                       +-----------------+
     | Response  +-----------------+  Send    ^  |
     +-----------|     Prepare     | Response |  | Command
                 |     Response    |----------+  | Received
                 +-----------------+             V
                            ^          +-----------------+
                    Command |          |   Processing    |
                  Processed +----------|     Command     |
                                       +-----------------+

              Figure 1: EPP Server State Machine

  EPP commands fall into three categories: session management commands,
  query commands, and data transform commands.  Session management
  commands are used to establish and end persistent sessions with an
  EPP server.  Query commands are used to perform read-only object
  information retrieval operations.  Transform commands are used to
  perform read-write object management operations.




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  Commands are processed by a server in the order they are received
  from a client.  Though an immediate response confirming receipt and
  processing of the command is produced by the server, the protocol
  includes features that allow for offline review of transform commands
  before the requested action is actually completed.  In such
  situations the response from the server MUST clearly note that the
  command has been received and processed, but the requested action is
  pending.  The state of the corresponding object MUST clearly reflect
  processing of the pending action.  The server MUST also notify the
  client when offline processing of the action has been completed.
  Object mappings SHOULD describe standard formats for notices that
  describe completion of offline processing.

  EPP uses XML namespaces to provide an extensible object management
  framework and to identify schemas required for XML instance parsing
  and validation.  These namespaces and schema definitions are used to
  identify both the base protocol schema and the schemas for managed
  objects.  The specific strings used to associate URIs and namespaces
  (such as the string "foo" in "xmlns:foo") in EPP are illustrative and
  are not needed for interoperability.

  All XML instances SHOULD begin with an <?xml?> declaration to
  identify the version of XML that is being used, optionally identify
  use of the character encoding used, and optionally provide a hint to
  an XML parser that an external schema file is needed to validate the
  XML instance.  Conformant XML parsers recognize both UTF-8 (defined
  in RFC 2279 [RFC2279]) and UTF-16 (defined in RFC 2781 [RFC2781]);
  per RFC 2277 [RFC2277] UTF-8 is the RECOMMENDED character encoding
  for use with EPP.

  Character encodings other than UTF-8 and UTF-16 are allowed by XML.
  UTF-8 is the default encoding assumed by XML in the absence of an
  "encoding" attribute or a byte order mark (BOM), thus the "encoding"
  attribute in the XML declaration is OPTIONAL if UTF-8 encoding is
  used.

  Normative section 4.3.3 and non-normative appendix F of [XML]
  describe use of a BOM to identify the character encoding in the
  absence of an XML declaration or encapsulating headers.  Appendix F
  includes a BOM to represent UTF-8 encoding, though section 4.3.3
  notes that a BOM is not needed to identify UTF-8 encoding.  Section
  4.3.3 was later amended (see [XMLE]) to clarify that a BOM MAY be
  used to identify UTF-8 encoding.  EPP clients and servers MUST accept
  a UTF-8 BOM if present, though emitting a UTF-8 BOM is NOT
  RECOMMENDED.






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  Example XML declarations:

  <?xml version="1.0" encoding="UTF-8" standalone="no"?>

  <?xml version="1.0" standalone="no"?>

  <?xml version="1.0" encoding="UTF-8"?>

  <?xml version="1.0"?>

2.1.  Transport Mapping Considerations

  As described previously, EPP can be layered over multiple transport
  protocols.  There are, however, a common set of considerations that
  MUST be addressed by any transport mapping defined for EPP.  These
  include:

  -  The transport mapping MUST preserve command order.

  -  The transport mapping MUST address the relationship between
     sessions and the client-server connection concept.

  -  The transport mapping MUST preserve the stateful nature of the
     protocol.

  -  The transport mapping MUST frame data units.

  -  The transport mapping MUST be onto a transport such as TCP
     [RFC793] or SCTP [RFC2960] that provides congestion avoidance that
     follows RFC 2914 [RFC2914], or if it maps onto a protocol such as
     SMTP [RFC2821] or BEEP [RFC3080], then the performance issues need
     to take into account issues of overload, server availability and
     so forth.

  -  The transport mapping MUST ensure reliability.

  -  The transport mapping MUST explicitly allow or prohibit
     pipelining.

  Pipelining, also known as command streaming, is when a client sends
  multiple commands to a server without waiting for each corresponding
  response.  After sending the commands, the client waits for the
  responses to arrive in the order corresponding to the completed
  commands.  Performance gains can sometimes be realized with
  pipelining, especially with high latency transports, but there are
  additional considerations associated with defining a transport
  mapping that supports pipelining:




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  -  Commands MUST be processed independent of each other.

  -  Depending on the transport, pipelining MAY be possible in the form
     of sending a complete session in a well-defined "batch".

  -  The transport mapping MUST describe how an error in processing a
     command affects continued operation of the session.

  A transport mapping MUST explain how all of these requirements are
  met given the transport protocol being used to exchange data.

2.2.  Protocol Identification

  All EPP XML instances MUST begin with an <epp> element.  This element
  identifies the start of an EPP protocol element, the namespace used
  within the protocol, and the location of the protocol schema.  The
  <epp> start element and the associated </epp> ending element MUST be
  applied to all structures sent by both clients and servers.

  Example "start" and "end" EPP elements:

  <epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
       epp-1.0.xsd">
  </epp>

2.3.  Hello Format

  EPP MAY be carried over both connection-oriented and connection-less
  transport protocols.  An EPP client MAY request a <greeting> from an
  EPP server at any time by sending a <hello> to a server.  Use of this
  element is essential in a connection-less environment where a server
  can not return a <greeting> in response to a client-initiated
  connection.  An EPP <hello> MUST be an empty element with no child
  elements.

  Example <hello>:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <hello/>
  C:</epp>





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2.4.  Greeting Format

  An EPP server responds to a successful connection and <hello> element
  by returning a <greeting> element to the client.  An EPP greeting
  contains the following elements:

  -  An <svID> element that contains the name of the server.

  -  An <svDate> element that contains the server's current date and
     time in UTC.

  -  An <svcMenu> element that identifies the services supported by the
     server, including:

  -  One or more <version> elements that identify the protocol versions
     supported by the server.

  -  One or more <lang> elements that contain the identifiers of the
     text response languages known by the server.  Language identifiers
     MUST be structured as documented in [RFC3066].

  -  One or more <objURI> elements that contain namespace URIs
     representing the objects that the server is capable of managing.
     A server MAY limit object management privileges on a per-client
     basis.

  -  An OPTIONAL <svcExtension> element that contains one or more
     <extURI> elements that contain namespace URIs representing object
     extensions supported by the server.

  -  A <dcp> (data collection policy) element that contains child
     elements used to describe the server's privacy policy for data
     collection and management.  Policy implications usually extend
     beyond the client-server relationship.  Both clients and servers
     can have relationships with other entities that need to know the
     server operator's data collection policy to make informed
     provisioning decisions.  Policy information MUST be disclosed to
     provisioning entities, though the method of disclosing policy data
     outside of direct protocol interaction is beyond the scope of this
     specification.  Child elements include the following:

  -  An <access> element that describes the access provided by the
     server to the client on behalf of the originating data source.
     The <access> element MUST contain one of the following child
     elements:

        <all/>: Access is given to all identified data.




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        <none/>: No access is provided to identified data.

        <null/>: Data is not persistent, so no access is possible.

        <personal/>: Access is given to identified data relating to
        individuals and organizational entities.

        <personalAndOther/>: Access is given to identified data
        relating to individuals, organizational entities, and other
        data of a non-personal nature.

        <other/>: Access is given to other identified data of a non-
        personal nature.

  -  One or more <statement> elements that describe data collection
     purposes, data recipients, and data retention.  Each <statement>
     element MUST contain a <purpose> element, a <recipient> element,
     and a <retention> element.

  The <purpose> element MUST contain one or more of the following child
  elements that describe the purposes for which data is collected:

     <admin/>: Administrative purposes.  Information can be used for
     administrative and technical support of the provisioning system.

     <contact/>: Contact for marketing purposes.  Information can be
     used to contact individuals, through a communications channel
     other than the protocol, for the promotion of a product or
     service.

     <prov/>: Object provisioning purposes.  Information can be used to
     identify objects and inter-object relationships.

     <other/>: Other purposes.  Information may be used in other ways
     not captured by the above definitions.

     The <recipient> element MUST contain one or more of the following
     child elements that describes the recipients of collected data:

        <other/>: Other entities following unknown practices.

        <ours>: Server operator and/or entities acting as agents or
        entities for whom the server operator is acting as an agent.
        An agent in this instance is defined as a third party that
        processes data only on behalf of the service provider for the
        completion of the stated purposes.  The <ours> element contains
        an OPTIONAL <recDesc> element that can be used to describe the
        recipient.



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        <public/>: Public forums.

        <same/>: Other entities following server practices.

        <unrelated/>: Unrelated third parties.

     The <retention> element MUST contain one of the following child
     elements that describes data retention practices:

        <business/>: Data persists per business practices.

        <indefinite/>: Data persists indefinitely.

        <legal/>: Data persists per legal requirements.

        <none/>: Data is not persistent, and is not retained for more
        than a brief period of time necessary to make use of it during
        the course of a single online interaction.

        <stated/>: Data persists to meet the stated purpose.

  -  An OPTIONAL <expiry> element that describes the lifetime of the
     policy.  The <expiry> element MUST contain one of the following
     child elements:

        <absolute/>: The policy is valid from the current date and time
        until it expires on the specified date and time.

        <relative/>: The policy is valid from the current date and time
        until the end of the specified duration.

  Data collection policy elements are based on work described in the
  World Wide Web Consortium's Platform for Privacy Preferences [P3P]
  specification.

















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  Example greeting:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <greeting>
  S:    <svID>Example EPP server epp.example.com</svID>
  S:    <svDate>2000-06-08T22:00:00.0Z</svDate>
  S:    <svcMenu>
  S:      <version>1.0</version>
  S:      <lang>en</lang>
  S:      <lang>fr</lang>
  S:      <objURI>urn:ietf:params:xml:ns:obj1</objURI>
  S:      <objURI>urn:ietf:params:xml:ns:obj2</objURI>
  S:      <objURI>urn:ietf:params:xml:ns:obj3</objURI>
  S:      <svcExtension>
  S:        <extURI>http://custom/obj1ext-1.0</extURI>
  S:      </svcExtension>
  S:    </svcMenu>
  S:    <dcp>
  S:      <access><all/></access>
  S:      <statement>
  S:        <purpose><admin/><prov/></purpose>
  S:        <recipient><ours/><public/></recipient>
  S:        <retention><stated/></retention>
  S:      </statement>
  S:    </dcp>
  S:  </greeting>
  S:</epp>

2.5.  Command Format

  An EPP client interacts with an EPP server by sending a command to
  the server and receiving a response from the server.  In addition to
  the standard EPP elements, an EPP command contains the following
  elements:

  -  A command element whose tag corresponds to one of the valid EPP
     commands described in this document.  The command element MAY
     contain either protocol-specified or object-specified child
     elements.

  -  An OPTIONAL <extension> element that MAY be used for server-
     defined command extensions.





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  -  An OPTIONAL <clTRID> (client transaction identifier) element that
     MAY be used to uniquely identify the command to the client.
     Clients are responsible for maintaining their own transaction
     identifier space to ensure uniqueness.

  Example command with object-specified child elements:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <info>
  C:      <obj:info xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <obj:name>example</obj:name>
  C:      </obj:info>
  C:    </info>
  C:    <clTRID>ABC-12345</clTRID>
  C:  </command>
  C:</epp>

2.6.  Response Format

  An EPP server responds to a client command by returning a response to
  the client.  EPP commands are atomic, so a command will either
  succeed completely or fail completely.  Success and failure results
  MUST NOT be mixed.  In addition to the standard EPP elements, an EPP
  response contains the following elements:

  -  One or more <result> elements that document the success or failure
     of command execution.  If the command was processed successfully,
     only one <result> element MUST be returned.  If the command was
     not processed successfully, multiple <result> elements MAY be
     returned to document failure conditions.  Each <result> element
     contains the following attribute and child elements:

     -  A "code" attribute whose value is a four-digit, decimal number
        that describes the success or failure of the command.

     -  A <msg> element containing a human-readable description of the
        response code.  The language of the response is identified via
        an OPTIONAL "lang" attribute.  If not specified, the default
        attribute value MUST be "en" (English).






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     -  Zero or more OPTIONAL <value> elements that identify a client-
        provided element (including XML tag and value) that caused a
        server error condition.

     -  Zero or more OPTIONAL <extValue> elements that can be used to
        provide additional error diagnostic information, including:

        -  A <value> element that identifies a client-provided element
           (including XML tag and value) that caused a server error
           condition.

        -  A <reason> element containing a human-readable message that
           describes the reason for the error.  The language of the
           response is identified via an OPTIONAL "lang" attribute.  If
           not specified, the default attribute value MUST be "en"
           (English).

  -  An OPTIONAL <msgQ> element that describes messages queued for
     client retrieval.  A <msgQ> element MUST NOT be present if there
     are no messages queued for client retrieval.  A <msgQ> element MAY
     be present in responses to EPP commands other than the <poll>
     command if messages are queued for retrieval.  A <msgQ> element
     MUST be present in responses to the EPP <poll> command if messages
     are queued for retrieval.  The <msgQ> element contains the
     following attributes:

  -  A "count" attribute that describes the number of messages that
     exist in the queue.

  -  An "id" attribute used to uniquely identify the message at the
     head of the queue.

  The <msgQ> element contains the following OPTIONAL child elements
  that MUST be returned in response to a <poll> request command and
  MUST NOT be returned in response to any other command, including a
  <poll> acknowledgement:

  -  A <qDate> element that contains the date and time that the message
     was enqueued.

  -  A <msg> element containing a human-readable message.  The language
     of the response is identified via an OPTIONAL "lang" attribute.
     If not specified, the default attribute value MUST be "en"
     (English).  This element MAY contain XML content for formatting
     purposes, but the XML content is not specified by the protocol and
     will thus not be processed for validity.





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  -  An OPTIONAL <resData> (response data) element that contains child
     elements specific to the command and associated object.

  -  An OPTIONAL <extension> element that MAY be used for server-
     defined response extensions.

  -  A <trID> (transaction identifier) element containing the
     transaction identifier assigned by the server to the command for
     which the response is being returned.  The transaction identifier
     is formed using the <clTRID> associated with the command if
     supplied by the client and a <svTRID> (server transaction
     identifier) that is assigned by and unique to the server.

     Transaction identifiers provide command-response synchronization
     integrity.  They SHOULD be logged, retained, and protected to
     ensure that both the client and the server have consistent
     temporal and state management records.

  Example response without <value> or <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg lang="en">Command completed successfully</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>
















Hollenbeck                  Standards Track                    [Page 14]

RFC 3730                          EPP                         March 2004


  Example response with <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:creData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <obj:name>example</obj:name>
  S:      </obj:creData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  Example response with error value elements:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="2004">
  S:      <msg>Parameter value range error</msg>
  S:      <value xmlns:obj="urn:ietf:params:xml:ns:obj">
  S:        <obj:elem1>2525</obj:elem1>
  S:      </value>
  S:    </result>
  S:    <result code="2005">
  S:      <msg>Parameter value syntax error</msg>
  S:      <value xmlns:obj="urn:ietf:params:xml:ns:obj">
  S:        <obj:elem2>ex(ample</obj:elem2>
  S:      </value>
  S:      <extValue>
  S:        <value xmlns:obj="urn:ietf:params:xml:ns:obj">
  S:          <obj:elem3>abc.ex(ample</obj:elem3>
  S:        </value>
  S:        <reason>Invalid character found.</reason>



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RFC 3730                          EPP                         March 2004


  S:      </extValue>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  Example response with notice of waiting server messages:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <msgQ count="5" id="12345"/>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  Command success or failure MUST NOT be assumed if no response is
  returned or if a returned response is malformed.  Protocol
  idempotency ensures the safety of retrying a command in cases of
  response delivery failure.

2.7.  Protocol Extension Framework

  EPP provides an extension framework that allows features to be added
  at the protocol, object, and command-response levels.

2.7.1.  Protocol Extension

  The EPP extension framework allows for definition of new protocol
  elements identified using XML namespace notation with a reference to
  an XML schema that defines the namespace.  The <epp> element that
  identifies the beginning of a protocol instance includes multiple
  child element choices, one of which is an <extension> element whose
  children define the extension.  For example, a protocol extension
  element would be described in generic terms as follows:




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RFC 3730                          EPP                         March 2004


  C:<epp>
  C:  <extension>
  C:    <!-- One or more extension elements. -->
  C:    <ext:foo xmlns:ext="urn:ietf:params:xml:ns:ext"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:ext ext.xsd">
  C:      <!-- One or more extension child elements. -->
  C:    </ext:foo>
  C:  </extension>
  C:</epp>

  This document does not define mappings for specific extensions.
  Extension specifications MUST be described in separate documents that
  define the objects and operations subject to the extension.

2.7.2.  Object Extension

  EPP provides an extensible object management framework that defines
  the syntax and semantics of protocol operations applied to a managed
  object.  This framework pushes the definition of each protocol
  operation into the context of a specific object, providing the
  ability to add mappings for new objects without having to modify the
  base protocol.

  Protocol elements that contain data specific to objects are
  identified using XML namespace notation with a reference to an XML
  schema that defines the namespace.  The schema for EPP supports use
  of dynamic object schemas on a per-command and per-response basis.
  For example, the start of an object-specific command element would be
  described in generic terms as follows:

  C:<EPPCommandName>
  C:  <object:command xmlns:object="urn:ietf:params:xml:ns:object"
  C:   xsi:schemaLocation="urn:ietf:params:xml:ns:object object.xsd">
  C:    <!-- One or more object-specific command elements. -->
  C:  </object:command>
  C:</EPPCommandName>

  An object-specific response element would be described similarly:

  S:<resData>
  S:  <object:resData xmlns:object="urn:ietf:params:xml:ns:object"
  S:   xsi:schemaLocation="urn:ietf:params:xml:ns:object object.xsd">
  S:    <!-- One or more object-specific response elements. -->
  S:  </object:resData>
  S:</resData>






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RFC 3730                          EPP                         March 2004


  This document does not define mappings for specific objects.  The
  mapping of EPP to an object MUST be described in separate documents
  that specifically address each command and response in the context of
  the object.  A suggested object mapping outline is included as an
  appendix to this document.

2.7.3.  Command-Response Extension

  EPP provides a facility for protocol command and response extensions.
  Protocol commands and responses MAY be extended by an <extension>
  element that contains additional elements whose syntax and semantics
  are not explicitly defined by EPP or an EPP object mapping.  This
  element is OPTIONAL.  Extensions are typically defined by agreement
  between client and server and MAY be used to extend EPP for unique
  operational needs.  A server-extended command element would be
  described in generic terms as follows:

  C:<command>
  C:  <!-- EPPCommandName can be "create", "update", etc. -->
  C:  <EPPCommandName>
  C:    <object:command xmlns:object="urn:ietf:params:xml:ns:object"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:object object.xsd">
  C:      <!-- One or more object-specific command elements. -->
  C:    </object:command>
  C:  </EPPCommandName>
  C:  <extension>
  C:    <!-- One or more server-defined elements. -->
  C:  </extension>
  C:</command>

  An server-extended response element would be described similarly:

  S:<response>
  S:  <result code="1000">
  S:    <msg lang="en">Command completed successfully</msg>
  S:  </result>
  S:  <extension>
  S:    <!-- One or more server-defined elements. -->
  S:  </extension>
  S:  <trID>
  S:    <clTRID>ABC-12345</clTRID>
  S:    <svTRID>54321-XYZ</svTRID>
  S:  </trID>
  S:</response>







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  This document does not define any specific server extensions.  The
  mapping of server extensions to EPP MUST be described in separate
  documents that specifically address extended commands and responses
  in the server's operational context.

2.8.  Object Identification

  Some objects, such as name servers and contacts, can have utility in
  multiple repositories.  However, maintaining disjoint copies of
  object information in multiple repositories can lead to
  inconsistencies that have adverse consequences for the Internet.  For
  example, changing a name server name in one repository, but not in a
  second repository that refers to the server for domain name
  delegation, can produce unexpected DNS query results.

  Globally unique identifiers can help facilitate object information
  sharing between repositories.  A globally unique identifier MUST be
  assigned to every object when the object is created; the identifier
  MUST be returned to the client as part of any request to retrieve the
  detailed attributes of an object.  Specific identifier values are a
  matter of repository policy, but they SHOULD be constructed according
  to the following algorithm:

  a) Divide the provisioning repository world into a number of object
     repository classes.

  b) Each repository within a class is assigned an identifier that is
     maintained by IANA.

  c) Each repository is responsible for assigning a unique local
     identifier for each object within the repository.

  d) The globally unique identifier is a concatenation of the local
     identifier, followed by a hyphen ("-", ASCII value 0x002D),
     followed by the repository identifier.

2.9.  Protocol Commands

  EPP provides commands to manage sessions, retrieve object
  information, and perform transformation operations on objects.  All
  EPP commands are atomic and designed so that they can be made
  idempotent, either succeeding completely or failing completely and
  producing predictable results in case of repeated execution.  This
  section describes each EPP command, including examples with
  representative server responses.






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RFC 3730                          EPP                         March 2004


2.9.1.  Session Management Commands

  EPP provides two commands for session management: <login> to
  establish a session with a server, and <logout> to end a session with
  a server.  The <login> command establishes an ongoing server session
  that preserves client identity and authorization information during
  the duration of the session.

2.9.1.1.  EPP <login> Command

  The EPP <login> command is used to establish a session with an EPP
  server in response to a greeting issued by the server.  A <login>
  command MUST be sent to a server before any other EPP command to
  establish an ongoing session.  A server operator MAY limit the number
  of failed login attempts N, 1 <= N <= infinity, after which a login
  failure results in the connection to the server (if a connection
  exists) being closed.

  A client identifier and initial password MUST be created on the
  server before a client can successfully complete a <login> command.
  The client identifier and initial password MUST be delivered to the
  client using an out-of-band method that protects the identifier and
  password from inadvertent disclosure.

  In addition to the standard EPP command elements, the <login> command
  contains the following child elements:

  -  A <clID> element that contains the client identifier assigned to
     the client by the server.

  -  A <pw> element that contains the client's plain text password.
     The value of this element is case sensitive.

  -  An OPTIONAL <newPW> element that contains a new plain text
     password to be assigned to the client for use with subsequent
     <login> commands.  The value of this element is case sensitive.

  -  An <options> element that contains the following child elements:

     -  A <version> element that contains the protocol version to be
        used for the command or ongoing server session.

     -  A <lang> element that contains the text response language to be
        used for the command or ongoing server session commands.

  The values of the <version> and <lang> elements MUST exactly match
  one of the values presented in the EPP greeting.




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RFC 3730                          EPP                         March 2004


  -  A <svcs> element that contains one or more <objURI> elements that
     contain namespace URIs representing the objects to be managed
     during the session.  The <svcs> element MAY contain an OPTIONAL
     <svcExtension> element that contains one or more <extURI> elements
     that identify object extensions to be used during the session.

  The PLAIN SASL mechanism presented in [RFC2595] describes a format
  for providing a user identifier, an authorization identifier, and a
  password as part of a single plain text string.  The EPP
  authentication mechanism is similar, though EPP does not require a
  session-level authorization identifier and the user identifier and
  password are separated into distinct XML elements.  Additional
  identification and authorization schemes MUST be provided at other
  protocol layers to provide more robust security services.

  Example <login> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <login>
  C:      <clID>ClientX</clID>
  C:      <pw>foo-BAR2</pw>
  C:      <newPW>bar-FOO2</newPW>
  C:      <options>
  C:        <version>1.0</version>
  C:        <lang>en</lang>
  C:      </options>
  C:      <svcs>
  C:        <objURI>urn:ietf:params:xml:ns:obj1</objURI>
  C:        <objURI>urn:ietf:params:xml:ns:obj2</objURI>
  C:        <objURI>urn:ietf:params:xml:ns:obj3</objURI>
  C:        <svcExtension>
  C:          <extURI>http://custom/obj1ext-1.0</extURI>
  C:        </svcExtension>
  C:      </svcs>
  C:    </login>
  C:    <clTRID>ABC-12345</clTRID>
  C:  </command>
  C:</epp>

  When a <login> command has been processed successfully, a server MUST
  respond with an EPP response with no <resData> element.  If
  successful, the server will respond by creating and maintaining a new
  session that SHOULD be terminated by a future <logout> command.



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RFC 3730                          EPP                         March 2004


  Example <login> response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <login> command is used to establish a session with an EPP
  server.  A <login> command MUST be rejected if received within the
  bounds of an existing session.  This action MUST be open to all
  authorized clients.

2.9.1.2.  EPP <logout> Command

  The EPP <logout> command is used to end a session with an EPP server.
  The <logout> command MUST be represented as an empty element with no
  child elements.

  A server MAY end a session due to client inactivity or excessive
  client session longevity.  The parameters for determining excessive
  client inactivity or session longevity are a matter of server policy
  and are not specified by this protocol.

  Transport mappings MUST explicitly describe any connection-oriented
  processing that takes place after processing a <logout> command and
  ending a session.














Hollenbeck                  Standards Track                    [Page 22]

RFC 3730                          EPP                         March 2004


  Example <logout> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <logout/>
  C:    <clTRID>ABC-12345</clTRID>
  C:  </command>
  C:</epp>

  When a <logout> command has been processed successfully, a server
  MUST respond with an EPP response with no <resData> element.  If
  successful, the server MUST also end the current session.

  Example <logout> response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1500">
  S:      <msg>Command completed successfully; ending session</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <logout> command is used to end a session with an EPP server.
  A <logout> command MUST be rejected if the command has not been
  preceded by a successful <login> command.  This action MUST be open
  to all authorized clients.

2.9.2.  Query Commands

  EPP provides four commands to retrieve object information: <check> to
  determine if an object can be provisioned within a repository, <info>
  to retrieve detailed information associated with a known object,
  <poll> to receive service notifications from the server, and
  <transfer> to retrieve object transfer status information.




Hollenbeck                  Standards Track                    [Page 23]

RFC 3730                          EPP                         March 2004


2.9.2.1.  EPP <check> Command

  The EPP <check> command is used to determine if an object can be
  provisioned within a repository.  It provides a hint that allows a
  client to anticipate the success or failure of provisioning an object
  using the <create> command as object provisioning requirements are
  ultimately a matter of server policy.

  The elements needed to identify an object are object-specific, so the
  child elements of the <check> command are specified using the EPP
  extension framework.  In addition to the standard EPP command
  elements, the <check> command contains the following child elements:

  -  An object-specific <obj:check> element that identify the objects
     to be queried.  Multiple objects of the same type MAY be queried
     within a single <check> command.

  Example <check> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <check>
  C:      <obj:check xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <obj:name>example1</obj:name>
  C:        <obj:name>example2</obj:name>
  C:        <obj:name>example3</obj:name>
  C:      </obj:check>
  C:    </check>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When a <check> command has been processed successfully, a server MUST
  respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific, though the EPP <resData> element MUST contain a
  child <obj:chkData> element that contains one or more <obj:cd> (check
  data) elements.  Each <obj:cd> elements contains the following child
  elements:






Hollenbeck                  Standards Track                    [Page 24]

RFC 3730                          EPP                         March 2004


  -  An object-specific element that identifies the queried object.
     This element MUST contain an "avail" attribute whose value
     indicates object availability (can it be provisioned or not) at
     the moment the <check> command was completed.  A value of "1" or
     "true" means that the object can be provisioned.  A value of "0"
     or "false" means that the object can not be provisioned.

  -  An OPTIONAL <obj:reason> element that MAY be provided when an
     object can not be provisioned.  If present, this element contains
     server-specific text to help explain why the object can not be
     provisioned.  This text MUST be represented in the response
     language previously negotiated with the client; an OPTIONAL "lang"
     attribute MAY be present to identify the language if the
     negotiated value is something other than the default value of "en"
     (English).

  Example <check> response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:chkData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <obj:cd>
  S:          <obj:name avail="1">example1</obj:name>
  S:        </obj:cd>
  S:        <obj:cd>
  S:          <obj:name avail="0">example2</obj:name>
  S:          <obj:reason>In use</obj:reason>
  S:        </obj:cd>
  S:        <obj:cd>
  S:          <obj:name avail="1">example3</obj:name>
  S:        </obj:cd>
  S:      </obj:chkData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>



Hollenbeck                  Standards Track                    [Page 25]

RFC 3730                          EPP                         March 2004


  The EPP <check> command is used to determine if an object can be
  provisioned within a repository.  This action MUST be open to all
  authorized clients.

2.9.2.2.  EPP <info> Command

  The EPP <info> command is used to retrieve information associated
  with an existing object.  The elements needed to identify an object
  and the type of information associated with an object are both
  object-specific, so the child elements of the <info> command are
  specified using the EPP extension framework.  In addition to the
  standard EPP command elements, the <info> command contains the
  following child elements:

  -  An object-specific <obj:info> element that identifies the object
     to be queried.

  Example <info> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <info>
  C:      <obj:info xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:info>
  C:    </info>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When an <info> command has been processed successfully, a server MUST
  respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema and the Repository Object Identifier (ROID) that was
  assigned to the object when the object was created.  Other child
  elements of the <resData> element are object-specific.










Hollenbeck                  Standards Track                    [Page 26]

RFC 3730                          EPP                         March 2004


  Example <info> response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:infData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <obj:roid>EXAMPLE1-REP</obj:roid>
  S:        <!-- Object-specific elements. -->
  S:      </obj:infData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <info> command is used to retrieve information associated
  with an existing object.  This action SHOULD be limited to authorized
  clients; restricting this action to the sponsoring client is
  RECOMMENDED.

2.9.2.3.  EPP <poll> Command

  The EPP <poll> command is used to discover and retrieve service
  messages queued by a server for individual clients.  If the message
  queue is not empty, a successful response to a <poll> command MUST
  return the first message from the message queue.  Each response
  returned from the server includes a server-unique message identifier
  that MUST be provided to acknowledge receipt of the message, and a
  counter that indicates the number of messages in the queue.  After a
  message has been received by the client, the client MUST respond to
  the message with an explicit acknowledgement to confirm that the
  message has been received.  A server MUST dequeue the message and
  decrement the queue counter after receiving acknowledgement from the
  client, making the next message in the queue (if any) available for
  retrieval.






Hollenbeck                  Standards Track                    [Page 27]

RFC 3730                          EPP                         March 2004


  Servers can occasionally perform actions on objects that are not in
  direct response to a client request, or an action taken by one client
  can indirectly involve a second client.  Examples of such actions
  include deletion upon expiration, automatic renewal upon expiration,
  and transfer coordination; other types of service information MAY be
  defined as a matter of server policy.  Service messages MUST be
  created for all clients affected by an action on an object.  For
  example, <transfer> actions MUST be reported to both the client that
  requests an object transfer and the client that has the authority to
  approve or reject the transfer request.

  Message queues can consume server resources if clients do not
  retrieve and acknowledge messages on a regular basis.  Servers MAY
  implement other mechanisms to dequeue and deliver messages if queue
  maintenance needs exceed server resource consumption limits.  Server
  operators SHOULD consider time-sensitivity and resource management
  factors when selecting a delivery method for service information
  because some message types can be reasonably delivered using non-
  protocol methods that require fewer server resources.

  Some of the information returned in response to a <poll> command can
  be object-specific, so some child elements of the <poll> response MAY
  be specified using the EPP extension framework.  The <poll> command
  MUST be represented as an empty element with no child elements.  An
  "op" attribute with value "req" is REQUIRED to retrieve the first
  message from the server message queue.  An "op" attribute (with value
  "ack") and a "msgID" attribute (whose value corresponds to the value
  of the "id" attribute copied from the <msg> element in the message
  being acknowledged) are REQUIRED to acknowledge receipt of a message.

  Example <poll> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <poll op="req"/>
  C:    <clTRID>ABC-12345</clTRID>
  C:  </command>
  C:</epp>

  The returned result code notes that a message has been dequeued and
  returned in response to a <poll> command.






Hollenbeck                  Standards Track                    [Page 28]

RFC 3730                          EPP                         March 2004


  Example <poll> response with object-specific information:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1301">
  S:      <msg>Command completed successfully; ack to dequeue</msg>
  S:    </result>
  S:    <msgQ count="5" id="12345">
  S:      <qDate>2000-06-08T22:00:00.0Z</qDate>
  S:      <msg>Transfer requested.</msg>
  S:    </msgQ>
  S:    <resData>
  S:      <obj:trnData
  S:       xmlns:obj="urn:ietf:params:xml:ns:obj-1.0"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj-1.0
  S:       obj-1.0.xsd">
  S:        <obj:name>example.com</obj:name>
  S:        <obj:trStatus>pending</obj:trStatus>
  S:        <obj:reID>ClientX</obj:reID>
  S:        <obj:reDate>2000-06-08T22:00:00.0Z</obj:reDate>
  S:        <obj:acID>ClientY</obj:acID>
  S:        <obj:acDate>2000-06-13T22:00:00.0Z</obj:acDate>
  S:        <obj:exDate>2002-09-08T22:00:00.0Z</obj:exDate>
  S:      </obj:trnData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  A client MUST acknowledge each response to dequeue the message and
  make subsequent messages available for retrieval.













Hollenbeck                  Standards Track                    [Page 29]

RFC 3730                          EPP                         March 2004


  Example <poll> acknowledgement command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <poll op="ack" msgID="12345"/>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  A <poll> acknowledgement response notes the number of messages
  remaining in the queue and the ID of the next message available for
  retrieval.

  Example <poll> acknowledgement response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <msgQ count="4" id="12346"/>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  Service messages can also be returned without object information.














Hollenbeck                  Standards Track                    [Page 30]

RFC 3730                          EPP                         March 2004


  Example <poll> response with mixed message content and without
  object-specific information:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1301">
  S:      <msg>Command completed successfully; ack to dequeue</msg>
  S:    </result>
  S:    <msgQ count="4" id="12346">
  S:      <qDate>2000-06-08T22:10:00.0Z</qDate>
  S:      <msg lang="en">Credit balance low.
  S:        <limit>100</limit><bal>5</bal>
  S:      </msg>
  S:    </msgQ>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The returned result code and message is used to note an empty server
  message queue.

  Example <poll> response to note an empty message queue:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1300">
  S:      <msg>Command completed successfully; no messages</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>






Hollenbeck                  Standards Track                    [Page 31]

RFC 3730                          EPP                         March 2004


  The EPP <poll> command is used to discover and retrieve client
  service messages from a server.  This action SHOULD be limited to
  authorized clients; queuing service messages and limiting queue
  access on a per-client basis is RECOMMENDED.

2.9.2.4.  EPP <transfer> Query Command

  The EPP <transfer> command provides a query operation that allows a
  client to determine real-time status of pending and completed
  transfer requests.  The elements needed to identify an object that is
  the subject of a transfer request are object-specific, so the child
  elements of the <transfer> query command are specified using the EPP
  extension framework.  In addition to the standard EPP command
  elements, the <transfer> command contains an "op" attribute with
  value "query", and the following child elements:

  -  An object-specific <obj:transfer> element that identifies the
     object whose transfer status is requested.

  Transfer status is typically considered sensitive information by the
  clients involved in the operation.  Object mappings MUST provide
  features to restrict transfer queries to authorized clients, such as
  by requiring authorization information as part of the request.

  Example <transfer> query command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <transfer op="query">
  C:      <obj:transfer xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:transfer>
  C:    </transfer>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When a <transfer> query command has been processed successfully, a
  server MUST respond with an EPP <resData> element that MUST contain a
  child element that identifies the object namespace and the location
  of the object schema.  The child elements of the <resData> element
  are object-specific, but they MUST include elements that identify the
  object, the status of the transfer, the identifier of the client that



Hollenbeck                  Standards Track                    [Page 32]

RFC 3730                          EPP                         March 2004


  requested the transfer, the date and time that the request was made,
  the identifier of the client that is authorized to act on the
  request, the date and time by which an action is expected, and an
  OPTIONAL date and time noting changes in the object's validity period
  (if applicable) that occur as a result of the transfer.

  Example <transfer> query response:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:trnData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <obj:name>example</obj:name>
  S:        <obj:trStatus>pending</obj:trStatus>
  S:        <obj:reID>ClientX</obj:reID>
  S:        <obj:reDate>2000-06-08T22:00:00.0Z</obj:reDate>
  S:        <obj:acID>ClientY</obj:acID>
  S:        <obj:acDate>2000-06-13T22:00:00.0Z</obj:acDate>
  S:        <obj:exDate>2002-09-08T22:00:00.0Z</obj:exDate>
  S:      </obj:trnData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <transfer> command provides a query operation that allows a
  client to determine real-time status of pending and completed
  transfer requests.  This action SHOULD be limited to authorized
  clients; restricting queries to the requesting and responding clients
  is RECOMMENDED.  Object transfer MAY be unavailable or limited by
  object-specific policies.









Hollenbeck                  Standards Track                    [Page 33]

RFC 3730                          EPP                         March 2004


2.9.3.  Object Transform Commands

  EPP provides five commands to transform objects: <create> to create
  an instance of an object with a server, <delete> to remove an
  instance of an object from a server, <renew> to extend the validity
  period of an object, <update> to change information associated with
  an object, and <transfer> to manage changes in client sponsorship of
  an object.

2.9.3.1.  EPP <create> Command

  The EPP <create> command is used to create an instance of an object.
  An object can be created for an indefinite period of time, or an
  object can be created for a specific validity period.  The EPP
  mapping for an object MUST describe the status of an object with
  respect to time, to include expected client and server behavior if a
  validity period is used.

  The elements needed to identify an object and associated attributes
  are object-specific, so the child elements of the <create> command
  are specified using the EPP extension framework.  In addition to the
  standard EPP command elements, the <create> command contains the
  following child elements:

  -  An object-specific <obj:create> element that identifies the object
     to be created and the elements that are required to create the
     object.

  Example <create> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <create>
  C:      <obj:create xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:create>
  C:    </create>
  C:    <clTRID>ABC-12345</clTRID>
  C:  </command>
  C:</epp>






Hollenbeck                  Standards Track                    [Page 34]

RFC 3730                          EPP                         March 2004


  When a <create> command has been processed successfully, a server MAY
  respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific.

  Example <create> response with <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:creData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <!-- Object-specific elements. -->
  S:      </obj:creData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12345</clTRID>
  S:      <svTRID>54321-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <create> command is used to create an instance of an object.
  This action SHOULD be limited to authorized clients and MAY be
  restricted on a per-client basis.

2.9.3.2.  EPP <delete> Command

  The EPP <delete> command is used to remove an instance of an existing
  object.  The elements needed to identify an object are object-
  specific, so the child elements of the <delete> command are specified
  using the EPP extension framework.  In addition to the standard EPP
  command elements, the <delete> command contains the following child
  elements:

  -  An object-specific <obj:delete> element that identifies the object
     to be deleted.






Hollenbeck                  Standards Track                    [Page 35]

RFC 3730                          EPP                         March 2004


  Example <delete> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <delete>
  C:      <obj:delete xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:delete>
  C:    </delete>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When a <delete> command has been processed successfully, a server MAY
  respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific.

  Example <delete> response without <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <delete> command is used to remove an instance of an existing
  object.  This action SHOULD be limited to authorized clients;
  restricting this action to the sponsoring client is RECOMMENDED.






Hollenbeck                  Standards Track                    [Page 36]

RFC 3730                          EPP                         March 2004


2.9.3.3.  EPP <renew> Command

  The EPP <renew> command is used to extend the validity period of an
  existing object.  The elements needed to identify and extend the
  validity period of an object are object-specific, so the child
  elements of the <renew> command are specified using the EPP extension
  framework.  In addition to the standard EPP command elements, the
  <renew> command contains the following child elements:

  -  An object-specific <obj:renew> element that identifies the object
     to be renewed and the elements that are required to extend the
     validity period of the object.

  Example <renew> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <renew>
  C:      <obj:renew xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:renew>
  C:    </renew>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When a <renew> command has been processed successfully, a server MAY
  respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific.

  Example <renew> response with <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>



Hollenbeck                  Standards Track                    [Page 37]

RFC 3730                          EPP                         March 2004


  S:    <resData>
  S:      <obj:renData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <!-- Object-specific elements. -->
  S:      </obj:renData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <renew> command is used to extend the validity period of an
  existing object.  This action SHOULD be limited to authorized
  clients; restricting this action to the sponsoring client is
  RECOMMENDED.  Object renewal MAY be unavailable or limited by
  object-specific policies.

2.9.3.4.  EPP <transfer> Command

  The EPP <transfer> command is used to manage changes in client
  sponsorship of an existing object.  Clients can initiate a transfer
  request, cancel a transfer request, approve a transfer request, and
  reject a transfer request using the "op" command attribute.

  A client who wishes to assume sponsorship of a known object from
  another client uses the <transfer> command with the value of the "op"
  attribute set to "request".  Once a transfer has been requested, the
  same client can cancel the request using a <transfer> command with
  the value of the "op" attribute set to "cancel".  A request to cancel
  the transfer MUST be sent to the server before the current sponsoring
  client either approves or rejects the transfer request and before the
  server automatically processes the request due to responding client
  inactivity.

  Once a transfer request has been received by the server, the server
  MUST notify the current sponsoring client of the requested transfer
  by queuing a service message for retrieval via the <poll> command.
  The current status of a pending <transfer> command for any object can
  be found using the <transfer> query command.  Transfer service
  messages MUST include the object-specific elements specified for
  <transfer> command responses.








Hollenbeck                  Standards Track                    [Page 38]

RFC 3730                          EPP                         March 2004


  The current sponsoring client MAY explicitly approve or reject the
  transfer request.  The client can approve the request using a
  <transfer> command with the value of the "op" attribute set to
  "approve".  The client can reject the request using a <transfer>
  command with the value of the "op" attribute set to "reject".

  A server MAY automatically approve or reject all transfer requests
  that are not explicitly approved or rejected by the current
  sponsoring client within a fixed amount of time.  The amount of time
  to wait for explicit action and the default server behavior are local
  matters not specified by EPP, but they SHOULD be documented in a
  server-specific profile document that describes default server
  behavior for client information.

  Objects eligible for transfer MUST have associated authorization
  information that MUST be provided to complete a <transfer> command.
  The type of authorization information required is object-specific;
  passwords or more complex mechanisms based on public key cryptography
  are typical.

  The elements needed to identify and complete the transfer of an
  object are object-specific, so the child elements of the <transfer>
  command are specified using the EPP extension framework.  In addition
  to the standard EPP command elements, the <transfer> command contains
  the following child elements:

  -  An object-specific <obj:transfer> element that identifies the
     object to be transferred and the elements that are required to
     process the transfer command.

  Example <transfer> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <transfer op="request">
  C:      <obj:transfer xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:transfer>
  C:    </transfer>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>




Hollenbeck                  Standards Track                    [Page 39]

RFC 3730                          EPP                         March 2004


  When a <transfer> command has been processed successfully, a server
  MUST respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific, but they MUST include elements that identify the
  object, the status of the transfer, the identifier of the client that
  requested the transfer, the date and time that the request was made,
  the identifier of the client that is authorized to act on the
  request, the date and time by which an action is expected, and an
  OPTIONAL date and time noting changes in the object's validity period
  (if applicable) that occur as a result of the transfer.

  Example <transfer> response with <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1001">
  S:      <msg>Command completed successfully; action pending</msg>
  S:    </result>
  S:    <resData>
  S:      <obj:trnData xmlns:obj="urn:ietf:params:xml:ns:obj"
  S:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  S:        <obj:name>example</obj:name>
  S:        <obj:trStatus>pending</obj:trStatus>
  S:        <obj:reID>ClientX</obj:reID>
  S:        <obj:reDate>2000-06-08T22:00:00.0Z</obj:reDate>
  S:        <obj:acID>ClientY</obj:acID>
  S:        <obj:acDate>2000-06-13T22:00:00.0Z</obj:acDate>
  S:        <obj:exDate>2002-09-08T22:00:00.0Z</obj:exDate>
  S:      </obj:trnData>
  S:    </resData>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <transfer> command is used to manage changes in client
  sponsorship of an existing object.  This action SHOULD be limited to
  authorized clients; restricting <transfer> requests to a client other
  than the current sponsoring client, <transfer> approval requests to





Hollenbeck                  Standards Track                    [Page 40]

RFC 3730                          EPP                         March 2004


  the current sponsoring client, and <transfer> cancellation requests
  to the original requesting client is RECOMMENDED.  Object transfer
  MAY be unavailable or limited by object-specific policies.

2.9.3.5.  EPP <update> Command

  The EPP <update> command is used to change information associated
  with an existing object.  The elements needed to identify and modify
  an object are object-specific, so the child elements of the <update>
  command are specified using the EPP extension framework.  In addition
  to the standard EPP command elements, the <update> command contains
  the following child elements:

  -  An object-specific <obj:update> element that identifies the object
     to be updated and the elements that are required to modify the
     object.  Object-specific elements MUST identify values to be
     added, values to be removed, or values to be changed.

  Example <update> command:

  C:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  C:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  C:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  C:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  C:     epp-1.0.xsd">
  C:  <command>
  C:    <update>
  C:      <obj:update xmlns:obj="urn:ietf:params:xml:ns:obj"
  C:       xsi:schemaLocation="urn:ietf:params:xml:ns:obj obj.xsd">
  C:        <!-- Object-specific elements. -->
  C:      </obj:update>
  C:    </update>
  C:    <clTRID>ABC-12346</clTRID>
  C:  </command>
  C:</epp>

  When an <update> command has been processed successfully, a server
  MAY respond with an EPP <resData> element that MUST contain a child
  element that identifies the object namespace and the location of the
  object schema.  The child elements of the <resData> element are
  object-specific.










Hollenbeck                  Standards Track                    [Page 41]

RFC 3730                          EPP                         March 2004


  Example <update> response without <resData>:

  S:<?xml version="1.0" encoding="UTF-8" standalone="no"?>
  S:<epp xmlns="urn:ietf:params:xml:ns:epp-1.0"
  S:     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  S:     xsi:schemaLocation="urn:ietf:params:xml:ns:epp-1.0
  S:     epp-1.0.xsd">
  S:  <response>
  S:    <result code="1000">
  S:      <msg>Command completed successfully</msg>
  S:    </result>
  S:    <trID>
  S:      <clTRID>ABC-12346</clTRID>
  S:      <svTRID>54322-XYZ</svTRID>
  S:    </trID>
  S:  </response>
  S:</epp>

  The EPP <update> command is used to change information associated
  with an existing object.  This action SHOULD be limited to authorized
  clients; restricting this action to the sponsoring client is
  RECOMMENDED.

3.  Result Codes

  EPP result codes are based on the theory of reply codes described in
  section 4.2.1 of [RFC2821].  EPP uses four decimal digits to describe
  the success or failure of each EPP command.  Each of the digits of
  the reply have special significance.

  The first digit denotes command success or failure.  The second digit
  denotes the response category, such as command syntax or security.
  The third and fourth digits provide explicit response detail within
  each response category.

  There are two values for the first digit of the reply code:

  1yzz   Positive completion reply.  The command has been accepted and
  processed by the system without error.

  2yzz   Negative completion reply.  The command was not accepted and
  the requested action did not occur.









Hollenbeck                  Standards Track                    [Page 42]

RFC 3730                          EPP                         March 2004


  The second digit groups responses into one of six specific
  categories:

  x0zz   Protocol Syntax
  x1zz   Implementation-specific Rules
  x2zz   Security
  x3zz   Data Management
  x4zz   Server System
  x5zz   Connection Management

  The third and fourth digits provide response detail within the
  categories defined by the first and second digits.  Specific result
  codes are listed in the table below.

  Every EPP response MUST include a result code and a human-readable
  description of the result code.  The language used to represent the
  description MAY be identified using an instance of the "lang"
  attribute within the <msg> element.  If not specified, the default
  language is English, identified as "en".  A description of the
  structure of valid values for the "lang" attribute is described in
  [RFC3066].

  Response text MAY be translated into other languages, though the
  translation MUST preserve the meaning of the code as described here.
  Response code values MUST NOT be changed when translating text.

  Response text in the table below is enclosed in quotes to clearly
  mark the beginning and ending of each response string.  Quotes MUST
  NOT be used to delimit these strings when returning response text via
  the protocol.





















Hollenbeck                  Standards Track                    [Page 43]

RFC 3730                          EPP                         March 2004


  Successful command completion responses:

  Code    Response text in English
  ___________________________________

  1000    "Command completed successfully"
  This is the usual response code for a successfully completed command
  that is not addressed by any other 1xxx-series response code.

  1001    "Command completed successfully; action pending"
  This response code MUST be returned when responding to a command the
  requires offline activity before the requested action can be
  completed.  See section 2 for a description of other processing
  requirements.

  1300    "Command completed successfully; no messages"
  This response code MUST be returned when responding to a <poll>
  request command and the server message queue is empty.

  1301    "Command completed successfully; ack to dequeue"
  This response code MUST be returned when responding to a <poll>
  request command and a message has been retrieved from the server
  message queue.

  1500    "Command completed successfully; ending session"
  This response code MUST be returned when responding to a successful
  <logout> command.
























Hollenbeck                  Standards Track                    [Page 44]

RFC 3730                          EPP                         March 2004


  Command error responses:

  Code    Response text in English
  ___________________________________

  2000    "Unknown command"
  This response code MUST be returned when a server receives a command
  element that is not defined by EPP.

  2001    "Command syntax error"
  This response code MUST be returned when a server receives an
  improperly formed command element.

  2002    "Command use error"
  This response code MUST be returned when a server receives a properly
  formed command element, but the command can not be executed due to a
  sequencing or context error.  For example, a <logout> command can not
  be executed without having first completed a <login> command.

  2003    "Required parameter missing"
  This response code MUST be returned when a server receives a command
  for which a required parameter value has not been provided.

  2004    "Parameter value range error"
  This response code MUST be returned when a server receives a command
  parameter whose value is outside the range of values specified by the
  protocol.  The error value SHOULD be returned via a <value> element
  in the EPP response.

  2005    "Parameter value syntax error"
  This response code MUST be returned when a server receives a command
  containing a parameter whose value is improperly formed.  The error
  value SHOULD be returned via a <value> element in the EPP response.

  2100    "Unimplemented protocol version"
  This response code MUST be returned when a server receives a command
  element specifying a protocol version that is not implemented by the
  server.

  2101    "Unimplemented command"
  This response code MUST be returned when a server receives a valid
  EPP command element that is not implemented by the server.  For
  example, a <transfer> command can be unimplemented for certain object
  types.







Hollenbeck                  Standards Track                    [Page 45]

RFC 3730                          EPP                         March 2004


  2102    "Unimplemented option"
  This response code MUST be returned when a server receives a valid
  EPP command element that contains a protocol option that is not
  implemented by the server.

  2103    "Unimplemented extension"
  This response code MUST be returned when a server receives a valid
  EPP command element that contains a protocol command extension that
  is not implemented by the server.

  2104    "Billing failure"
  This response code MUST be returned when a server attempts to execute
  a billable operation and the command can not be completed due to a
  client billing failure.

  2105    "Object is not eligible for renewal"
  This response code MUST be returned when a client attempts to <renew>
  an object that is not eligible for renewal in accordance with server
  policy.

  2106    "Object is not eligible for transfer"
  This response code MUST be returned when a client attempts to
  <transfer> an object that is not eligible for transfer in accordance
  with server policy.

  2200    "Authentication error"
  This response code MUST be returned when a server notes an error when
  validating client credentials.

  2201    "Authorization error"
  This response code MUST be returned when a server notes a client
  authorization error when executing a command.  This error is used to
  note that a client lacks privileges to execute the requested command.

  2202    "Invalid authorization information"
  This response code MUST be returned when a server receives invalid
  command authorization information required to confirm authorization
  to execute a command.  This error is used to note that a client has
  the privileges required to execute the requested command, but the
  authorization information provided by the client does not match the
  authorization information archived by the server.

  2300    "Object pending transfer"
  This response code MUST be returned when a server receives a command
  to transfer an object that is pending transfer due to an earlier
  transfer request.





Hollenbeck                  Standards Track                    [Page 46]

RFC 3730                          EPP                         March 2004


  2301    "Object not pending transfer"
  This response code MUST be returned when a server receives a command
  to confirm, reject, or cancel the transfer an object when no command
  has been made to transfer the object.

  2302    "Object exists"
  This response code MUST be returned when a server receives a command
  to create an object that already exists in the repository.

  2303    "Object does not exist"
  This response code MUST be returned when a server receives a command
  to query or transform an object that does not exist in the
  repository.

  2304    "Object status prohibits operation"
  This response code MUST be returned when a server receives a command
  to transform an object that can not be completed due to server policy
  or business practices.  For example, a server can disallow <transfer>
  commands under terms and conditions that are matters of local policy,
  or the server might have received a <delete> command for an object
  whose status prohibits deletion.

  2305    "Object association prohibits operation"
  This response code MUST be returned when a server receives a command
  to transform an object that can not be completed due to dependencies
  on other objects that are associated with the target object.  For
  example, a server can disallow <delete> commands while an object has
  active associations with other objects.

  2306    "Parameter value policy error"
  This response code MUST be returned when a server receives a command
  containing a parameter value that is syntactically valid, but
  semantically invalid due to local policy.  For example, the server
  can support a subset of a range of valid protocol parameter values.
  The error value SHOULD be returned via a <value> element in the EPP
  response.

  2307    "Unimplemented object service"
  This response code MUST be returned when a server receives a command
  to operate on an object service that is not supported by the server.

  2308    "Data management policy violation"
  This response code MUST be returned when a server receives a command
  whose execution results in a violation of server data management
  policies.  For example, removing all attribute values or object
  associations from an object might be a violation of a server's data
  management policies.




Hollenbeck                  Standards Track                    [Page 47]

RFC 3730                          EPP                         March 2004


  2400    "Command failed"
  This response code MUST be returned when a server is unable to
  execute a command due to an internal server error that is not related
  to the protocol.  The failure can be transient.  The server MUST keep
  any ongoing session active.

  2500    "Command failed; server closing connection"
  This response code MUST be returned when a server receives a command
  that can not be completed due to an internal server error that is not
  related to the protocol.  The failure is not transient, and will
  cause other commands to fail as well.  The server MUST end the active
  session and close the existing connection.

  2501    "Authentication error; server closing connection"
  This response code MUST be returned when a server notes an error when
  validating client credentials and a server-defined limit on the
  number of allowable failures has been exceeded.  The server MUST
  close the existing connection.

  2502    "Session limit exceeded; server closing connection"
  This response code MUST be returned when a server receives a <login>
  command, and the command can not be completed because the client has
  exceeded a system-defined limit on the number of sessions that the
  client can establish.  It might be possible to establish a session by
  ending existing unused sessions and closing inactive connections.

4.  Formal Syntax

  EPP is specified in XML Schema notation.  The formal syntax presented
  here is a complete schema representation of EPP suitable for
  automated validation of EPP XML instances.

  Two schemas are presented here.  The first schema is the base EPP
  schema.  The second schema defines elements and structures that can
  be used by both the base EPP schema and object mapping schemas.  The
  BEGIN and END tags are not part of the schema; they are used to note
  the beginning and ending of the schema for URI registration purposes.














Hollenbeck                  Standards Track                    [Page 48]

RFC 3730                          EPP                         March 2004


4.1.  Base Schema

    BEGIN
    <?xml version="1.0" encoding="UTF-8"?>

    <schema targetNamespace="urn:ietf:params:xml:ns:epp-1.0"
            xmlns:epp="urn:ietf:params:xml:ns:epp-1.0"
            xmlns:eppcom="urn:ietf:params:xml:ns:eppcom-1.0"
            xmlns="http://www.w3.org/2001/XMLSchema"
            elementFormDefault="qualified">

    <!--
    Import common element types.
    -->
      <import namespace="urn:ietf:params:xml:ns:eppcom-1.0"
              schemaLocation="eppcom-1.0.xsd"/>

      <annotation>
        <documentation>
          Extensible Provisioning Protocol v1.0 schema.
        </documentation>
      </annotation>

    <!--
    Every EPP XML instance must begin with this element.
    -->
      <element name="epp" type="epp:eppType"/>

    <!--
    An EPP XML instance must contain a greeting, hello, command,
    response, or extension.
    -->
      <complexType name="eppType">
        <choice>
          <element name="greeting" type="epp:greetingType"/>
          <element name="hello"/>
          <element name="command" type="epp:commandType"/>
          <element name="response" type="epp:responseType"/>
          <element name="extension" type="epp:extAnyType"/>
        </choice>
      </complexType>

    <!--
    A greeting is sent by a server in response to a client connection
    or <hello>.
    -->
      <complexType name="greetingType">
        <sequence>



Hollenbeck                  Standards Track                    [Page 49]

RFC 3730                          EPP                         March 2004


          <element name="svID" type="epp:sIDType"/>
          <element name="svDate" type="dateTime"/>
          <element name="svcMenu" type="epp:svcMenuType"/>
          <element name="dcp" type="epp:dcpType"/>
        </sequence>
      </complexType>

    <!--
    Server IDs are strings with minimum and maximum length
    restrictions.
    -->
      <simpleType name="sIDType">
        <restriction base="normalizedString">
          <minLength value="3"/>
          <maxLength value="64"/>
        </restriction>
      </simpleType>

    <!--
    A server greeting identifies available object services.
    -->
      <complexType name="svcMenuType">
        <sequence>
          <element name="version" type="epp:versionType"
           maxOccurs="unbounded"/>
          <element name="lang" type="language"
           maxOccurs="unbounded"/>
          <element name="objURI" type="anyURI"
           maxOccurs="unbounded"/>
          <element name="svcExtension" type="epp:extURIType"
           minOccurs="0"/>
        </sequence>
      </complexType>

    <!--
    Data Collection Policy types.
    -->
      <complexType name="dcpType">
        <sequence>
          <element name="access" type="epp:dcpAccessType"/>
          <element name="statement" type="epp:dcpStatementType"
           maxOccurs="unbounded"/>
          <element name="expiry" type="epp:dcpExpiryType"
           minOccurs="0"/>
        </sequence>
      </complexType>

      <complexType name="dcpAccessType">



Hollenbeck                  Standards Track                    [Page 50]

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        <choice>
          <element name="all"/>
          <element name="none"/>
          <element name="null"/>
          <element name="other"/>
          <element name="personal"/>
          <element name="personalAndOther"/>
        </choice>
      </complexType>

      <complexType name="dcpStatementType">
        <sequence>
          <element name="purpose" type="epp:dcpPurposeType"/>
          <element name="recipient" type="epp:dcpRecipientType"/>
          <element name="retention" type="epp:dcpRetentionType"/>
        </sequence>
      </complexType>

      <complexType name="dcpPurposeType">
        <sequence>
          <element name="admin"
           minOccurs="0"/>
          <element name="contact"
           minOccurs="0"/>
          <element name="other"
           minOccurs="0"/>
          <element name="prov"
           minOccurs="0"/>
        </sequence>
      </complexType>

      <complexType name="dcpRecipientType">
        <sequence>
          <element name="other"
           minOccurs="0"/>
          <element name="ours" type="epp:dcpOursType"
           minOccurs="0" maxOccurs="unbounded"/>
          <element name="public"
           minOccurs="0"/>
          <element name="same"
           minOccurs="0"/>
          <element name="unrelated"
           minOccurs="0"/>
        </sequence>
      </complexType>

      <complexType name="dcpOursType">
        <sequence>



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          <element name="recDesc" type="epp:dcpRecDescType"
           minOccurs="0"/>
        </sequence>
      </complexType>

      <simpleType name="dcpRecDescType">
        <restriction base="token">
          <minLength value="1"/>
          <maxLength value="255"/>
        </restriction>
      </simpleType>

      <complexType name="dcpRetentionType">
        <choice>
          <element name="business"/>
          <element name="indefinite"/>
          <element name="legal"/>
          <element name="none"/>
          <element name="stated"/>
        </choice>
      </complexType>

      <complexType name="dcpExpiryType">
        <choice>
          <element name="absolute" type="dateTime"/>
          <element name="relative" type="duration"/>
        </choice>
      </complexType>

    <!--
    Extension framework types.
    -->
      <complexType name="extAnyType">
        <sequence>
          <any namespace="##other"
           maxOccurs="unbounded"/>
        </sequence>
      </complexType>

      <complexType name="extURIType">
        <sequence>
          <element name="extURI" type="anyURI"
           maxOccurs="unbounded"/>
        </sequence>
      </complexType>

    <!--
  An EPP version number is a dotted pair of decimal numbers.



Hollenbeck                  Standards Track                    [Page 52]

RFC 3730                          EPP                         March 2004


  -->
    <simpleType name="versionType">
      <restriction base="token">
        <pattern value="[1-9]+\.[0-9]+"/>
        <enumeration value="1.0"/>
      </restriction>
    </simpleType>

  <!--
  Command types.
  -->
    <complexType name="commandType">
      <sequence>
        <choice>
          <element name="check" type="epp:readWriteType"/>
          <element name="create" type="epp:readWriteType"/>
          <element name="delete" type="epp:readWriteType"/>
          <element name="info" type="epp:readWriteType"/>
          <element name="login" type="epp:loginType"/>
          <element name="logout"/>
          <element name="poll" type="epp:pollType"/>
          <element name="renew" type="epp:readWriteType"/>
          <element name="transfer" type="epp:transferType"/>
          <element name="update" type="epp:readWriteType"/>
        </choice>
        <element name="extension" type="epp:extAnyType"
         minOccurs="0"/>
        <element name="clTRID" type="epp:trIDStringType"
         minOccurs="0"/>
      </sequence>
    </complexType>

  <!--
  The <login> command.
  -->
    <complexType name="loginType">
      <sequence>
        <element name="clID" type="eppcom:clIDType"/>
        <element name="pw" type="epp:pwType"/>
        <element name="newPW" type="epp:pwType"
         minOccurs="0"/>
        <element name="options" type="epp:credsOptionsType"/>
        <element name="svcs" type="epp:loginSvcType"/>
      </sequence>
    </complexType>

    <complexType name="credsOptionsType">
      <sequence>



Hollenbeck                  Standards Track                    [Page 53]

RFC 3730                          EPP                         March 2004


        <element name="version" type="epp:versionType"/>
        <element name="lang" type="language"/>
      </sequence>
    </complexType>

    <simpleType name="pwType">
      <restriction base="token">
        <minLength value="6"/>
        <maxLength value="16"/>
      </restriction>
    </simpleType>

    <complexType name="loginSvcType">
      <sequence>
        <element name="objURI" type="anyURI"
         maxOccurs="unbounded"/>
        <element name="svcExtension" type="epp:extURIType"
         minOccurs="0"/>
      </sequence>
    </complexType>

  <!--
  The <poll> command.
  -->
    <complexType name="pollType">
      <attribute name="op" type="epp:pollOpType"
       use="required"/>
      <attribute name="msgID" type="token"/>
    </complexType>

    <simpleType name="pollOpType">
      <restriction base="token">
        <enumeration value="ack"/>
        <enumeration value="req"/>
      </restriction>
    </simpleType>
  <!--
  The <transfer> command.  This is object-specific, and uses attributes
  to identify the requested operation.
  -->
    <complexType name="transferType">
      <sequence>
        <any namespace="##other"/>
      </sequence>
      <attribute name="op" type="epp:transferOpType"
       use="required"/>
    </complexType>




Hollenbeck                  Standards Track                    [Page 54]

RFC 3730                          EPP                         March 2004


    <simpleType name="transferOpType">
      <restriction base="token">
        <enumeration value="approve"/>
        <enumeration value="cancel"/>
        <enumeration value="query"/>
        <enumeration value="reject"/>
        <enumeration value="request"/>
      </restriction>
    </simpleType>

  <!--
  All other object-centric commands. EPP doesn't specify the syntax or
  semantics of object-centric command elements.  The elements MUST be
  described in detail in another schema specific to the object.
  -->
    <complexType name="readWriteType">
      <sequence>
        <any namespace="##other"/>
      </sequence>
    </complexType>

    <complexType name="trIDType">
      <sequence>
        <element name="clTRID" type="epp:trIDStringType"
         minOccurs="0"/>
        <element name="svTRID" type="epp:trIDStringType"/>
      </sequence>
    </complexType>

    <simpleType name="trIDStringType">
      <restriction base="token">
        <minLength value="3"/>
        <maxLength value="64"/>
      </restriction>
    </simpleType>
  <!--
  Response types.
  -->
    <complexType name="responseType">
      <sequence>
        <element name="result" type="epp:resultType"
         maxOccurs="unbounded"/>
        <element name="msgQ" type="epp:msgQType"
         minOccurs="0"/>
        <element name="resData" type="epp:extAnyType"
         minOccurs="0"/>
        <element name="extension" type="epp:extAnyType"
         minOccurs="0"/>



Hollenbeck                  Standards Track                    [Page 55]

RFC 3730                          EPP                         March 2004


        <element name="trID" type="epp:trIDType"/>
      </sequence>
    </complexType>

    <complexType name="resultType">
      <sequence>
        <element name="msg" type="epp:msgType"/>
        <choice minOccurs="0" maxOccurs="unbounded">
          <element name="value" type="epp:errValueType"/>
          <element name="extValue" type="epp:extErrValueType"/>
        </choice>
      </sequence>
      <attribute name="code" type="epp:resultCodeType"
       use="required"/>
    </complexType>

    <complexType name="errValueType" mixed="true">
      <sequence>
        <any namespace="##any" processContents="skip"/>
      </sequence>
      <anyAttribute namespace="##any" processContents="skip"/>
    </complexType>

    <complexType name="extErrValueType">
      <sequence>
        <element name="value" type="epp:errValueType"/>
        <element name="reason" type="epp:msgType"/>
      </sequence>
    </complexType>

    <complexType name="msgQType">
      <sequence>
        <element name="qDate" type="dateTime"
         minOccurs="0"/>
        <element name="msg" type="epp:mixedMsgType"
         minOccurs="0"/>
      </sequence>
      <attribute name="count" type="unsignedLong"
       use="required"/>
      <attribute name="id" type="eppcom:minTokenType"
       use="required"/>
    </complexType>

    <complexType name="mixedMsgType" mixed="true">
      <sequence>
        <any processContents="skip"
         minOccurs="0" maxOccurs="unbounded"/>
      </sequence>



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      <attribute name="lang" type="language"
       default="en"/>
    </complexType>

  <!--
  Human-readable text may be expressed in languages other than English.
  -->
    <complexType name="msgType">
      <simpleContent>
        <extension base="normalizedString">
          <attribute name="lang" type="language"
           default="en"/>
        </extension>
      </simpleContent>
    </complexType>

  <!--
  EPP result codes.
  -->
    <simpleType name="resultCodeType">
      <restriction base="unsignedShort">
        <enumeration value="1000"/>
        <enumeration value="1001"/>
        <enumeration value="1300"/>
        <enumeration value="1301"/>
        <enumeration value="1500"/>
        <enumeration value="2000"/>
        <enumeration value="2001"/>
        <enumeration value="2002"/>
        <enumeration value="2003"/>
        <enumeration value="2004"/>
        <enumeration value="2005"/>
        <enumeration value="2100"/>
        <enumeration value="2101"/>
        <enumeration value="2102"/>
        <enumeration value="2103"/>
        <enumeration value="2104"/>
        <enumeration value="2105"/>
        <enumeration value="2106"/>
        <enumeration value="2200"/>
        <enumeration value="2201"/>
        <enumeration value="2202"/>
        <enumeration value="2300"/>
        <enumeration value="2301"/>
        <enumeration value="2302"/>
        <enumeration value="2303"/>
        <enumeration value="2304"/>
        <enumeration value="2305"/>



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        <enumeration value="2306"/>
        <enumeration value="2307"/>
        <enumeration value="2308"/>
        <enumeration value="2400"/>
        <enumeration value="2500"/>
        <enumeration value="2501"/>
        <enumeration value="2502"/>
      </restriction>
    </simpleType>

  <!--
  End of schema.
  -->
  </schema>
  END

4.2.  Shared Structure Schema

    BEGIN
    <?xml version="1.0" encoding="UTF-8"?>

    <schema targetNamespace="urn:ietf:params:xml:ns:eppcom-1.0"
            xmlns:eppcom="urn:ietf:params:xml:ns:eppcom-1.0"
            xmlns="http://www.w3.org/2001/XMLSchema"
            elementFormDefault="qualified">

      <annotation>
        <documentation>
        Extensible Provisioning Protocol v1.0
        shared structures schema.
      </documentation>
    </annotation>

  <!--
  Object authorization information types.
  -->
    <complexType name="pwAuthInfoType">
      <simpleContent>
        <extension base="normalizedString">
          <attribute name="roid" type="eppcom:roidType"/>
        </extension>
      </simpleContent>
    </complexType>

    <complexType name="extAuthInfoType">
      <sequence>
        <any namespace="##other"/>
      </sequence>



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    </complexType>

  <!--
  <check> response types.
  -->
    <complexType name="reasonType">
      <simpleContent>
        <extension base="eppcom:reasonBaseType">
          <attribute name="lang" type="language"/>
        </extension>
      </simpleContent>
    </complexType>

    <simpleType name="reasonBaseType">
      <restriction base="token">
        <minLength value="1"/>
        <maxLength value="32"/>
      </restriction>
    </simpleType>

  <!--
  Abstract client and object identifier type.
  -->
    <simpleType name="clIDType">
      <restriction base="token">
        <minLength value="3"/>
        <maxLength value="16"/>
      </restriction>
    </simpleType>

  <!--
  DNS label type.
  -->
    <simpleType name="labelType">
      <restriction base="token">
        <minLength value="1"/>
        <maxLength value="255"/>
      </restriction>
    </simpleType>

  <!--
  Non-empty token type.
  -->
    <simpleType name="minTokenType">
      <restriction base="token">
        <minLength value="1"/>
      </restriction>
    </simpleType>



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  <!--
  Repository Object IDentifier type.
  -->
    <simpleType name="roidType">
      <restriction base="token">
        <pattern value="(\w|_){1,80}-\w{1,8}"/>
      </restriction>
    </simpleType>

  <!--
  Transfer status identifiers.
  -->
    <simpleType name="trStatusType">
      <restriction base="token">
        <enumeration value="clientApproved"/>
        <enumeration value="clientCancelled"/>
        <enumeration value="clientRejected"/>
        <enumeration value="pending"/>
        <enumeration value="serverApproved"/>
        <enumeration value="serverCancelled"/>
      </restriction>
    </simpleType>

  <!--
  End of schema.
  -->
  </schema>
  END

5.  Internationalization Considerations

  EPP is represented in XML, which provides native support for encoding
  information using the Unicode character set and its more compact
  representations including UTF-8.  Conformant XML processors recognize
  both UTF-8 and UTF-16.  Though XML includes provisions to identify
  and use other character encodings through use of an "encoding"
  attribute in an <?xml?> declaration, use of UTF-8 is RECOMMENDED in
  environments where parser encoding support incompatibility exists.

  EPP includes a provision for returning a human-readable message with
  every result code.  This document describes result codes in English,
  but the actual text returned with a result MAY be provided in a
  language negotiated when a session is established.  Languages other
  than English MUST be noted through specification of a "lang"
  attribute for each message.  Valid values for the "lang" attribute
  and "lang" negotiation elements are described in [RFC3066].





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  All date-time values presented via EPP MUST be expressed in Universal
  Coordinated Time using the Gregorian calendar.  XML Schema allows use
  of time zone identifiers to indicate offsets from the zero meridian,
  but this option MUST NOT be used with EPP.  The extended date-time
  form using upper case "T" and "Z" characters defined in [RFC3339]
  MUST be used to represent date-time values as XML Schema does not
  support truncated date-time forms or lower case "T" and "Z"
  characters.

6.  IANA Considerations

  This document uses URNs to describe XML namespaces and XML schemas
  conforming to a registry mechanism described in [RFC3688].  Four URI
  assignments have been registered by the IANA.

  Registration request for the EPP namespace:

     URI: urn:ietf:params:xml:ns:epp-1.0

  Registrant Contact: See the "Author's Address" section of this
  document.

     XML: None.  Namespace URIs do not represent an XML specification.

  Registration request for the EPP XML schema:

     URI: urn:ietf:params:xml:schema:epp-1.0

  Registrant Contact: See the "Author's Address" section of this
  document.

     XML: See the "Base Schema" section of this document.

  Registration request for the EPP shared structure namespace:

     URI: urn:ietf:params:xml:ns:eppcom-1.0

  Registrant Contact: See the "Author's Address" section of this
  document.

     XML: None.  Namespace URIs do not represent an XML specification.

  Registration request for the EPP shared structure XML schema:

     URI: urn:ietf:params:xml:schema:eppcom-1.0






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  Registrant Contact: See the "Author's Address" section of this
  document.

     XML: See the "Shared Structure Schema" section of this document.

7.  Security Considerations

  EPP provides only simple client authentication services.  A passive
  attack is sufficient to recover client identifiers and passwords,
  allowing trivial command forgery.  Protection against most common
  attacks and more robust security services MUST be provided by other
  protocol layers.  Specifically, EPP instances MUST be protected using
  a transport mechanism or application protocol that provides integrity
  and confidentiality.

  EPP uses a variant of the PLAIN SASL mechanism described in [RFC2595]
  to provide a simple application-layer authentication service that
  augments or supplements authentication and identification services
  that might be available at other protocol layers.  Where the PLAIN
  SASL mechanism specifies provision of an authorization identifier,
  authentication identifier, and password as a single string separated
  by ASCII NUL characters, EPP specifies use of a combined
  authorization and authentication identifier and a password provided
  as distinct XML elements.

  Repeated password guessing attempts can be discouraged by limiting
  the number of <login> attempts that can be attempted on an open
  connection.  A server MAY close an open connection if multiple
  <login> attempts are made with either an invalid client identifier,
  an invalid password, or both an invalid client identifier and an
  invalid password.

  EPP uses authentication information associated with objects to
  confirm object transfer authority.  Authentication information
  exchanged between EPP clients and third party entities MUST be
  exchanged using a facility that provides privacy and integrity
  services to protect against unintended disclosure and modification
  while in transit.

8.  Acknowledgements

  This document was originally written as an individual submission
  Internet-Draft.  The provreg working group later adopted it as a
  working group document and provided many invaluable comments and
  suggested improvements.  The author wishes to acknowledge the efforts
  of WG chairs Edward Lewis and Jaap Akkerhuis for their process and
  editorial contributions.




Hollenbeck                  Standards Track                    [Page 62]

RFC 3730                          EPP                         March 2004


  Specific suggestions that have been incorporated into this document
  were provided by Chris Bason, Eric Brunner-Williams, Jordyn Buchanan,
  Roger Castillo Cortazar, Dave Crocker, Ayesha Damaraju, Sheer El-
  Showk, Patrik Faltstrom, James Gould, John Immordino, Dan Kohn, Hong
  Liu, Klaus Malorny, Dan Manley, Michael Mealling, Patrick Mevzek,
  Andrew Newton, Budi Rahardjo, Asbjorn Steira, Rick Wesson, and Jay
  Westerdal.

9.  References

9.1.  Normative References

  [RFC2119]  Bradner, S., "Key Words for Use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

  [RFC2277]  Alvestrand, H., "IETF Policy on Character Sets and
             Languages", BCP 18, RFC 2277, January 1998.

  [RFC2279]  Yergeau, F., "UTF-8, a transformation format of ISO
             10646", RFC 2279, January 1998.

  [RFC2781]  Hoffman, P. and F. Yergeau, "UTF-16, an encoding of ISO
             10646", RFC 2781, February 2000.

  [RFC2914]  Floyd, S., "Congestion Control Principles", BCP 41, RFC
             2914, September 2000.

  [RFC3023]  Murata, M., St.Laurent, S. and D. Kohn, "XML Media Types",
             RFC 3023, January 2001.

  [RFC3066]  Alvestrand, H., "Tags for the Identification of
             Languages", BCP 47, RFC 3066, January 2001.

  [RFC3339]  Klyne, G. and C. Newman, "Date and Time on the Internet:
             Timestamps", RFC 3339, July 2002.

  [RFC3375]  Hollenbeck, S., "Generic Registry-Registrar Protocol
             Requirements", RFC 3375, September 2002.

  [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
             January 2004.

  [XML]      Editor T. Bray et al.: "Extensible Markup Language (XML)
             1.0 (Second Edition)", W3C Recommendation 6 October 2000.

  [XMLE]     "XML 1.0 Second Edition Specification Errata", E22, 25
             July 2001, http://www.w3.org/XML/xml-V10-2e-errata#E22.




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RFC 3730                          EPP                         March 2004


  [XMLS-1]   Editors H. Thompson et al.: "XML Schema Part 1:
             Structures", W3C Recommendation 2 May 2001.

  [XMLS-2]   Editors P. Biron, A. Malhotra: "XML Schema Part 2:
             Datatypes", W3C Recommendation 2 May 2001.

9.2.  Informative References

  [P3P]      Editor M. Marchiori: "The Platform for Privacy Preferences
             1.0 (P3P1.0) Specification", W3C Recommendation 16 April
             2002.

  [RFC793]   Postel, J., "Transmission Control Protocol", STD 7, RFC
             793, September 1981.

  [RFC2595]  Newman, C., "Using TLS with IMAP, POP3 and ACAP", RFC
             2595, June 1999.

  [RFC2821]  Klensin, J., Ed., "Simple Mail Transfer Protocol", RFC
             2821, April 2001.

  [RFC2960]  Stewart, R., Xie, Q., Morneault, K., Sharp, C.,
             Schwarzbauer, H., Taylor, T., Rytina, I., Kalla, M.,
             Zhang, L. and V. Paxson,  "Stream Control Transmission
             Protocol", RFC 2960, October 2000.

  [RFC3080]  Rose, M., "The Blocks Extensible Exchange Protocol Core",
             RFC 3080, March 2001.























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Appendix A:  Object Mapping Template

  This appendix describes a recommended outline for documenting the EPP
  mapping of an object.  Documents that describe EPP object mappings
  SHOULD describe the mapping in a format similar to the one used here.
  Additional sections are required if the object mapping is written in
  Internet-Draft or RFC format.

1.  Introduction

  Provide an introduction that describes the object and an overview of
  the mapping to EPP.

2.  Object Attributes

  Describe the attributes associated with the object, including
  references to syntax specifications as appropriate.  Examples of
  object attributes include a name or identifier and dates associated
  with modification events.

3.  EPP Command Mapping

3.1.  EPP Query Commands

3.1.1.  EPP <check> Command

  Describe the object-specific mappings required to implement the EPP
  <check> command.  Include both sample commands and sample responses.

3.1.2.  EPP <info> Command

  Describe the object-specific mappings required to implement the EPP
  <info> command.  Include both sample commands and sample responses.

3.1.3.  EPP <poll> Command

  Describe the object-specific mappings required to implement the EPP
  <poll> command.  Include both sample commands and sample responses.

3.1.4.  EPP <transfer> Command

  Describe the object-specific mappings required to implement the EPP
  <transfer> query command.  Include both sample commands and sample
  responses.







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3.2.  EPP Transform Commands

3.2.1.  EPP <create> Command

  Describe the object-specific mappings required to implement the EPP
  <create> command.  Include both sample commands and sample responses.
  Describe the status of the object with respect to time, including
  expected client and server behavior if a validity period is used.

3.2.2.  EPP <delete> Command

  Describe the object-specific mappings required to implement the EPP
  <delete> command.  Include both sample commands and sample responses.

3.2.3.  EPP <renew> Command

  Describe the object-specific mappings required to implement the EPP
  <renew> command.  Include both sample commands and sample responses.

3.2.4.  EPP <transfer> Command

  Describe the object-specific mappings required to implement the EPP
  <transfer> command.  Include both sample commands and sample
  responses.

3.2.5.  EPP <update> Command

  Describe the object-specific mappings required to implement the EPP
  <update> command.  Include both sample commands and sample responses.

4.  Formal Syntax

  Provide the XML schema for the object mapping.  An XML DTD MUST NOT
  be used as DTDs do not provide sufficient support for XML namespaces
  and strong data typing.
















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Appendix B:  Media Type Registration: application/epp+xml

  MIME media type name: application

  MIME subtype name: epp+xml

  Mandatory parameters: none

  Optional parameters: Same as the charset parameter of application/xml
  as specified in [RFC3023].

  Encoding considerations: Same as the encoding considerations of
  application/xml as specified in [RFC3023].

  Security considerations: This type has all of the security
  considerations described in [RFC3023] plus the considerations
  specified in the Security Considerations section of this document.

  Interoperability considerations: XML has proven to be interoperable
  across WebDAV clients and servers, and for import and export from
  multiple XML authoring tools.  For maximum interoperability,
  validating processors are recommended.  Although non-validating
  processors can be more efficient, they are not required to handle all
  features of XML.  For further information, see sub-section 2.9
  "Standalone Document Declaration" and section 5 "Conformance" of
  [XML].

  Published specification: This document.

  Applications which use this media type: EPP is device-, platform-,
  and vendor-neutral and is supported by multiple service providers.

  Additional information: If used, magic numbers, fragment identifiers,
  base URIs, and use of the BOM should be as specified in [RFC3023].

  Magic number(s): None.  File extension(s): .xml Macintosh File  Type
  Code(s): "TEXT"

  Person and email address for further information: See the "Author's
  Address" section of this document.

  Intended usage: COMMON

  Author/Change controller: IETF







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RFC 3730                          EPP                         March 2004


Author's Address

  Scott Hollenbeck
  VeriSign Global Registry Services
  21345 Ridgetop Circle
  Dulles, VA 20166-6503
  USA

  EMail: [email protected]










































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Full Copyright Statement

  Copyright (C) The Internet Society (2004).  This document is subject
  to the rights, licenses and restrictions contained in BCP 78 and
  except as set forth therein, the authors retain all their rights.

  This document and the information contained herein are provided on an
  "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
  OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
  ENGINEERING TASK FORCE DISCLAIM 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.

Intellectual Property

  The IETF takes no position regarding the validity or scope of any
  Intellectual Property Rights or other rights that might be claimed to
  pertain to the implementation or use of the technology described in
  this document or the extent to which any license under such rights
  might or might not be available; nor does it represent that it has
  made any independent effort to identify any such rights.  Information
  on the procedures with respect to rights in RFC documents can be
  found in BCP 78 and BCP 79.

  Copies of IPR disclosures made to the IETF Secretariat and any
  assurances of licenses to be made available, or the result of an
  attempt made to obtain a general license or permission for the use of
  such proprietary rights by implementers or users of this
  specification can be obtained from the IETF on-line IPR repository at
  http://www.ietf.org/ipr.

  The IETF invites any interested party to bring to its attention any
  copyrights, patents or patent applications, or other proprietary
  rights that may cover technology that may be required to implement
  this standard.  Please address the information to the IETF at ietf-
  [email protected].

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.









Hollenbeck                  Standards Track                    [Page 69]