Network Working Group                                      C. Allocchio
Request for Comments: 2162                             I.N.F.N. - Italy
Obsoletes: 1405                                            January 1998
Category: Experimental


          MaXIM-11 - Mapping between X.400 / Internet mail
                                 and
                             Mail-11 mail

Status of this Memo

  This memo defines an Experimental Protocol for the Internet
  community.  It does not specify an Internet standard of any kind.
  Discussion and suggestions for improvement are requested.
  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (1998).  All Rights Reserved.

Abstract

  This document describes a set of mappings which will enable inter
  working between systems operating the ISO/IEC 10021 - CCITT (now ITU)
  X.400 Recommendations on Message Handling Systems, and systems
  running the Mail-11 (also known as DECnet mail or VMSmail) protocol.
  The specifications are valid both within DECnet Phase IV and
  DECnet/OSI addressing and routing scheme.

  The complete scenario of X.400 / MIME / Mail-11 is also considered,
  in order to cover the possible complex cases arising in multiple
  gateway translations.

  This document covers mainly the X.400 O/R address to/from Mail-11
  address mapping and the RFC822 to/from Mail-11 ones; other mappings
  are based on MIXER specifications. Bodypart mappings are not
  specified in this document: MIXER and MIME-MHS specifications can be
  applied to map bodyparts between X.400, MIME and Mail-11, too. In
  fact MIME encoding can be used without modifications within Mail-11
  text bodyparts.

  This document obsoletes RFC 1405, which was a combined effort of
  TERENA Working Group on Messaging, and the IETF X.400 Ops Working
  Group. This update was prepared by IETF MIXER working group.






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Chapter 1 - Introduction

1.1. X.400

  The standard referred shortly into this document as "X.400" relates
  to the ISO/IEC 10021 - CCITT 1984, 1988 and 1992 X.400 Series
  Recommendations covering the Message Oriented Text Interchange
  Service (MOTIS). This document covers the Inter Personal Messaging
  System (IPMS) only.

1.2. Mail-11

  Mail-11, also known as DECnet mail and often improperly referred as
  VMSmail, is the proprietary protocol implemented by Digital Equipment
  Corporation (DEC) to establish a real-time text messaging system
  among systems implementing the DECnet Phase IV and DECnet/OSI (CLNS)
  networking protocols.

1.3. RFC822 / MIME

  RFC822 was defined as a standard for personal messaging systems
  within the DARPA Internet and is now diffused on top of many
  different message transfer protocols, like SMTP, UUCP, BITNET, JNT
  Grey Book, CSnet. MIME specifications allows transport of non-textual
  information into RFC822 messages. Their mapping with X.400 is fully
  described in MIXER and MIME-MHS. In this document we will consider
  their relations with Mail-11, too.

1.4. The user community

  The community using MIME or X.400 messaging system is currently
  growing in the whole world, but there is still a number of very large
  communities using Mail-11 based messaging systems willing to
  communicate easily with X.400 based Message Handling Systems and with
  MIME based systems. Among these large DECnet based networks we can
  include the High Energy Physics network (HEPnet) and the Space
  Physics Analysis Network (SPAN).

  Many other local communities actively use internally Mail-11 mailing
  protocols. As any other "non standard" mail protocol, using non
  standard mapping techniques between Mail-11 and standard mail systems
  can produce unpredictable results.

  For these reasons a set of rules covering conversion between Mail-11
  and X.400 or MIME is described in this document.






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  This document also covers the case of Mail-11 systems implementing
  the "foreign mail protocol" allowing Mail-11 to interface other mail
  systems, including RFC822 based system.

Chapter 2 - Message Elements

2.1. Service Elements

  Mail-11 protocol offers a very restricted set of elements composing a
  Inter Personal Message (IPM), whereas X.400 and RFC822/MIME
  specifications support a complex and large amount of service
  elements.  Considering the case where a message is relayed between
  two X.400 MHS or MIME Message Transport System (MTS) via a Mail-11
  messaging system this could result in a nearly complete loss of
  information.

  To minimise the inconvenience, any of the X.400 or MIME service
  elements which do not map directly into Mail-11 equivalent ones
  accordingly to this specification, will be included into Mail-11 text
  body parts as an additional RFC822-like header; this additional
  header will be inserted between the Mail-11 P2 headers (From:, To:,
  CC:, Subj:) and the other Mail-11 bodyparts. In particular, X.400
  elements will also be at first converted into textual representation
  before insertion.

  An example, where a multimedia message has been encoded into mail-11
  after having crossed also a MIME-MHS (MIXER conformant) gateway:

    From:  smtp%"[email protected]"  "Erik"  18-OCT-1994 13:55:00.49
    To:    ALLOCCHIO
    CC:    smtp%"[email protected]"
    Subj:  enjoy this nice picture!

    X400-Originator: [email protected]
    X400-Recipients: [email protected], [email protected]
    Sender: Erik Newmann <[email protected]>
    Organisation: SURFnet bv
    Mime-Version: 1.0
    Content-Type: multipart/mixed; boundary="----- =_aaaaaa0"
    Content-ID: <[email protected]>

    ------- =_aaaaaa0
    Content-Type: text/plain; charset="us-ascii"
    Content-ID: <[email protected]>

    look... you never saw this one!!
    I just include the picture in the next bodypart
    and I hope you get it fine.



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    regards,

    Erik                                         (continues...)

    ------- =_aaaaaa0                            (continued...)
    Content-Type: image/gif
    Content-ID: <[email protected]>
    Content-Description: a nice snapshot!
    Content-Transfer-Encoding: base64

    RAV8372FAASD83D721NSHDHD3ASDFJKHWEHKJHCBASDFA829CA8SDB29B132RBAKDFA
    9KSJ2KJAA0SDFNAL20DDKFALJ20AJDLFB239B9SC9B29BA9BDFADSDF03998ASDFASD

    ------- =_aaaaaa0

  We need, in fact, to consider also the case when a message originates
  from a network implementing RFC822/MIME protocols and is relayed via
  Mail-11 to an X.400 MHS, or vice versa.

  Whenever any X.400 element not covered in this specification needs to
  be converted into textual representation (to be included into a
  Mail-11 RFC822-like header or text bodypart) we will apply the rules
  specified in MIXER (X.400 to RFC822/MIME sections).

  Vice versa, MIXER specification (RFC822/MIME to X.400 sections) also
  gives the correct rules to convert from textual representations
  contained into Mail-11 RFC822-like header or bodyparts into X.400
  elements.

  On the other hand, RFC822/MIME headers not covered by this
  specification are included 'as they are' into Mail-11 RFC822-like
  header and bodyparts. The way back from Mail-11 to RFC822/MIME
  structure becomes thus straightforward.

  The above methods assures maximum transparency and minimal or null
  loss of information also when Mail-11 is involved.















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2.2. Mail-11 service elements to X.400 service elements.

  All envelope (P1) and header (P2) Mail-11 service elements are
  supported in the conversion to X.400. Note that Mail-11 P1 is solely
  composed by P1-11.From and P1-11.To, and any other Mail-11 element
  belongs to Mail-11 P2:

       - P1-11.From
               maps to P1.Originator

       - P1-11.To
               maps to P1.Primary Recipient

       - P2-11.'From:'
               usually maps to P2.Originator (see section 2.6)

       - P2-11.'To:'
               maps to P2.Primary Recipient

       - P2-11.'CC:'
               maps to P2.Copy Recipient

       - P2-11.Date
               maps to P2.Submission Time Stamp

       - P2-11.'Subj:'
               maps to P2.Subject

  Any eventual RFC822-like text header in Mail-11 body part will be
  interpreted as specified into MIXER.

2.3. X.400 service elements to Mail-11 service elements

  The following X.400 service elements are supported directly into
  Mail-11 conversion:

       - P1.Originator
               maps to P1-11.'From:'

       - P1.Primary Recipients
               maps to P1-11.'To:'

       - P2.Originator
               usually maps to P2-11.'From:' (see section 2.6)

       - P2.Primary Recipients
               maps to P2-11.'To:'




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       - P2.Copy Recipients
               maps to P2-11.'CC:'

       - P2.Submission Time Stamp
               maps to P2-11.Date

       - P2.Subject
               maps to P2-11.'Subj:'

  The following X.400 service element is partially supported into
  Mail-11 conversion:

       - P2.Blind Copy Recipient
               to ensure the required privacy, when a message contains
               a BCC address, the following actions occurs:
               - a new message is created, containing the body parts;
               - a new envelope is added to the new message, containing
                 the originator and the BCC recipient addresses only;
               - a note is added to the message informing the BCC
                 recipient about the fact that the message was a BCC;
               - the new message is delivered separately;
               - a note is added to the message delivered to TO and CC
                 recipients informing them about the fact that there
                 were some BCC recipients, too.

  Any other X.400 service element support is done accordingly to MIXER
  including the mapped element into the RFC822-like header into Mail-11
  body part.

2.4. Mail-11 service elements to RFC822/MIME service elements.

  All envelope (P1) and header (P2) Mail-11 service elements are
  supported in the conversion to RFC822/MIME:

       - P1-11.From
               maps to 822-MTS.Originator

       - P1-11.To
               maps to 822-MTS.Primary Recipient

       - P2-11.'From:'
               usually maps to 822.'From:' (see section 2.6)

       - P2-11.'To:'
               maps to 822.'To:'

       - P2-11.'CC:'
               maps to 822.'Cc:'



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       - P2-11.Date
               maps to 822.'Date:'

       - P2-11.'Subj:'
               maps to 822.'Subject:'

  Any eventual RFC822-like text header in Mail-11 body part will be
  re-inserted into RFC822/MIME message 'as it is'.

2.5. RFC822/MIME service elements to Mail-11 service elements

  The following RFC822 service elements are supported directly into
  Mail-11 conversion:

       - 822-MTS.Originator
               maps to P1-11.From

       - 822-MTS.Primary Recipients
               maps to P1-11.To

       - 822.'From:'
               usually maps to P2-11.'From:' (see section 2.5)

       - 822.'To:'
               maps to P2-11.'To:'

       - 822.'Cc:'
               maps to P2-11.'CC:'

       - 822.'Date:'
               maps to P2-11.Date

       - 822.'Subject:'
               maps to P2-11.'Subj:'

















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  The following RFC822 service element is partially supported into
  Mail-11 conversion:

       - 822.'Bcc:'
               to ensure the required privacy, when a message contains
               a BCC address, the following actions occurs:
               - a new message is created, containing the body parts;
               - a new envelope is added to the new message, containing
                 the originator and the BCC recipient addresses only;
               - a note is added to the message informing the BCC
                 recipient about the fact that the message was a BCC;
               - the new message is delivered separately;
               - a note is added to the message delivered to TO and CC
                 recipients informing them about the fact that there
                 were some BCC recipients, too.

  Any other RFC822/MIME service element support is done simply
  including the element 'as it is' into the RFC822-like header and into
  a Mail-11 body part.

2.6. Rules to define the Mail-11 P2-11.'From:' element

  Mail-11 User Agents (usually VMSmail) uses the P2-11.'From:' element
  as destination in case the REPLY command is issued, ignoring any
  other specification like 'Sender:' 'Reply-To:' 'Return-Path:' etc.
  Also a number of automatic responders uses this field only to address
  their messages.

  Is it thus essential to insert into this field the correct
  information, i.e. the correct address where, according to X.400 or
  RFC822 rules the REPLY command or any automatically generated message
  should go.

  The rules specified in RFC822, section 4.4.4 should be used as a
  selection criterion to define the content of this field.

  In particular, in case the P2-11.'From:' element is not generated
  from the P2.Originator (X.400) or from the 822.'From:' (RFC822), it
  is essential to preserve into a 'From:' record of the RFC822-like
  header the original information contained into the P2.Originator or
  822.'From:' fields.










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  Vice versa, when converting from Mail-11 into X.400 or RFC822/MIME
  the information contained into the 'From:' field of the RFC822-like
  header (if present) will supersede the one contained into the Mail-11
  P2-11.'From:'. An example:

    From:  smtp%"[email protected]"  "Erik"  18-OCT-1994 13:55:00.49
    To:    ALLOCCHIO
    CC:    smtp%"[email protected]"
    Subj:  enjoy this nice picture!

    From: Erik Newmann <[email protected]>
    Reply-To: [email protected]
    Organisation: SURFnet bv
    Message-Id: <[email protected]>

  when converting back into RFC822 the header will be:

    From: Erik Newmann <[email protected]>
    Reply-To: [email protected]
    To: [email protected]
    Cc: [email protected]
    Subject: enjoy this nice picture!
    Organisation: SURFnet bv
    Message-Id: <[email protected]>

  The described method, although violating canonical conversion
  principles, assures the maximum functionality to the users, and
  provides consistency in case of multiple conversions for a single
  message.

Chapter 3 - Basic Mappings

  The basic mappings indicated in MIXER and its updates should be fully
  used.

  A special consideration must be used for encoding RFC822 addresses
  containing quotes '"' into Mail-11. In fact Mail-11 addresses cannot
  contain that special character, as it is reserved to delimit "quoted
  strings" themselves, as when using the Mail-11 foreign mail protocol.
  An example:

     "John Poe"@Mixergw.local.ca.us    (RFC822)

  cannot be included in a Mail-11 foreign mail protocol address 'as
  is', due to the quotes in the LHS section. Quotes must thus be
  encoded.  MIXER specifies exactly how to encode quotes and other
  characters when translating RFC822 addresses into X.400. Mail-11
  addresses are not limited to printablestring, as for X.400, but a



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  subset of the MIXER encoding can be used for the quotes character,
  and, as a direct consequence, for open and closed round brackets '('
  and ')':

     smtp%"(q)John Poe(q)@Mixergw.local.ca.us"

Chapter 4 - Addressing - Mail-11 / X.400

4.1. Mail-11 addressing

  Mail-11 addressing can vary from a very simple case up to complex
  ones, if there are other Mail-11 to "something-else" gateways
  involved. In any case a Mail-11 address is an ASCII string composed
  of different elements.

4.2. X.400 addressing

  On the other hand, An X.400 O/R address is a collection of
  attributes, which can anyway be presented as an IA5 textual
  representation as defined in RFC1685 and CCITT F.401, Annex B.

4.3. Mail-11 address components

  Let us start defining the different parts composing a Mail-11
  address. Mail-11 addresses syntax is slightly different between Phase
  IV and DECnet/OSI cases:

  - Phase IV:  we consider a Mail-11 address as composed by 3 parts:

       [route] [node::] local-part

  where 'route' and 'node' are optional and only 'local-part' is
  compulsory.

  - DECnet/OSI: we consider a Mail-11 address as composed by 3 parts:

       [net:] [node-clns::] local-part

  where 'net and 'node-clns' are optional and only 'local-part' is
  compulsory.

  Here comes a formal definition of these elements

    node = *(ALPHA/DIGIT) / *DIGIT / *DIGIT "." *DIGIT

    route = *(node "::")

    subdomain = *(ALPHA/DIGIT)



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    node-clns = *("." subdomain)

    net = *(ALPHA/DIGIT)

    local-part = username / nickname / for-protocol

    username = *(ALPHA/DIGIT)

    nickname = <printablestring - <" " and HTAB>>

    for-protocol = (f-pref f-sep <">f-address<">)

    f-pref = *(ALPHA/DIGIT)

    f-sep = "%" / "::"

    f-address = printablestring / RFC822-address / X400-text-address

    X400-text-address = <textual representation of an X.400 O/R addr>

    Please note that in x400-text-address both the ";" notation and the
    "/" notation are equivalent and allowed (see examples in different
    sect.)

       Some examples (Phase IV):

          route           node    local-part
          -----------------------------------------------------------
                                  USER47
                          MYNODE::BETTY
          BOSTON::CLUS02::GOOFY1::MARY34
                                  IN%"[email protected]"
                  UCLA13::MVAX93::MRGATE::"MBOX1::MBX34::MYC3::BOB"
                          MIAMI2::George.Rosenthal
                  CCUBVX::VS3100::Jnet%"IAB3425@IBAX23L"
                                  MRGATE::"C=xx::A=bbb::P=ppp::S=Joe"
                          MAINVX::IN%"path1!path2!user%dom"
                          GWX400::gw%"C=xx;ADMD=aaa;PRMD=ppp;S=Lee;"
                          GX409A::x400%"/C=xx/A=aaa/P=ppp/S=Lee"
                                  smtp%"[email protected]"
                  MICKEY::PRFGAT::profs%"NANCY@IBMB"
                                  edu%"HU427BD%[email protected]"









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  Some examples (DECnet/OSI):

     net  node              local-part
     -----------------------------------------------------------
                             USER47
          .IT.MYDOM1.MYNODE::BETTY
     OMNI:.US.GOV.LB.GOOFY1::MARY34
                             IN%"[email protected]"
     NET1:.SALES.ADM.MVAX93::MRGATE::"MBOX1::MBX34::MYC3::BOB"
            .FR.LYON.MIAMI2::George.Rosenthal
          .AU.ABXY2W.VS3100::Jnet%"IAB3425@IBAX23L"
                             MRGATE::"C=xx::A=bbb::P=ppp::S=Joe"
      INT:.GB.3LABV56.MAINV::IN%"path1!path2!user%dom"
                     GWX400::gw%"C=xx;ADMD=aaa;PRMD=ppp;S=Lee;"
                             smtp%"[email protected]"
     OMNI:.DE.TEST.V1.GWY32::GX409A::x400%"/C=xx/A=aaa/P=ppp/S=Lee"

  Note that also in DECnet/OSI there can be Phase IV like node names,
  the so called "Phase IV compatibility node names", but no 'route'
  term is allowed in front of them. In case the address consists of a
  DECnet/OSI 'net' and/or 'node' specification, plus an old Phase IV
  node address (like the last one in above examples) we consider the
  old Phese IV node name (GX409A) as 'local-part'.

Chapter 5 - Mapping - Mail-11 / X.400

5.1. Mapping scheme

  DECnet phase IV address field is somehow a 'flat land' with some
  obliged routes to reach some hidden areas. Thus a truly hierarchical
  mapping scheme using mapping rules as suitable for RFC822 is not the
  appropriate solution. A fixed set of encoding rules using DDAs
  support is defined in order to define the mapping.

  DECnet/OSI address field is, on the other hand, hyerarchical,
  implementing a real domain style organization, resembling very
  closely the RFC822 domain addresses. However also in DECnet/OSI
  networks the old Phase IV flat addresing schema remains valid,
  expecially for the so called 'Phase IV short aliases'. For this
  reason, and to keep mapping as simple as possible, the same set of
  fixed rules usind DDAs encoding will be used both for Phase IV and
  DECnet/OSI addresses.









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  Another important aspect of the problem is the coexistence in DECnet
  phase IV of many disjoint networks, using the same DECnet address
  space, i.e., common X.400 and/or RFC822 mailing system acting as glue
  to connect different isolated Mail-11 islands. In DECnet/OSI this
  aspect is more canonically approached, introducing the concept of
  'net', a unique name identifying the single internally fully
  interconnected DECnet network sharing the same DECnet/OSI name space.

  To identify uniquely each DECnet Phase IV network we will thus extend
  the concept of DECnet/OSI 'net' also to this case. We define as 'net'
  in Phase IV a unique ASCII string identifying the DECnet network we
  are connected to. If the Phase IV network is already migrating and
  thus interconnected to DECnet/OSI areas, the 'net' identifier already
  used in the DECnet/OSI areas is automatically extended to the whole
  DECnet community.

  If the network still uses Phase IV protocols only, a 'net' identifier
  must be chosen. In this case the 'net' element will identify the
  DECnet community being served, but it could also differ from the
  actual official network name. It is reccommended that the same 'net'
  identifier will be adopted unmodified when the eventual migration to
  DECnet/OSI will take place within that DECnet community.

  Aliases are allowed for the 'net' identifier. Some well known
  identifiers and aliases:

      net = 'OMNI'         the High Energy Physics & Space Physics
                           DECnet network;

  aliases:

      net = 'HEPnet'       alias for 'OMNI'
      net = 'SPAN'         alias for 'OMNI'

  The need of labelling each DECnet network with its name comes also
  from the requirement to implement the 'intelligent' gateway, i.e.,
  the gateway which is able to understand its ability to connect
  directly to the specified DECnet network, even if the O/R address
  specify a path to a different gateway. A more detailed discussion of
  the problem is in 5.3 and 5.5.











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  A registry of 'net' attributes to insure uniqueness of names must be
  established: this registry is the same one created for migration to
  DECnet/OSI. A simple table coupling 'net' and the gateway address is
  also used, in a syntax similar to the 'gate1' and 'gate2' tables used
  in MIXER. An example:

       OMNI#[email protected]$infn.ADMD$garr.C$IT#
       OMNI#O$ESRIN1.PRMD$esa.ADMD$Master400.C$it#
       HEPnet#[email protected]$infn.ADMD$garr.C$IT#
       HEPnet#O$ESRIN1.PRMD$esa.ADMD$Master400.C$it#
       SPAN#[email protected]$infn.ADMD$garr.C$IT#
       SPAN#O$ESRIN1.PRMD$esa.ADMD$Master400.C$it#

  Ambiguous left entries are allowed. Gateway implementations could
  simply choose among one of the specified gateways, or try them all in
  cyclic order to obtain better performances.

  Note that aliases are established using this gate table, too: simply
  add equivalent entries into the table, like the 'HEPnet' and 'SPAN'
  entries. Aliases, however, must be used only to enable users to use
  commonly used names, but any  gateway implementing this specification
  must generate addresses with official 'net' names, only ('OMNI' for
  the above table).

  The Mail-11 gateways table, however, just constitutes the list of the
  the appropriate MIXER address translation) RFC822 world. Any other
  gateway implementing this specification (and the related ones) should
  use its local name as first choice for the Mail-11 'net' it can
  reach, and use the official Mail-11 gateway table to reach only the
  non connected ones. This list of Mail-11 gateway entries is supposed
  to contain the list of 'net' tags and their aliases; as this list is
  usually small, currently we do not take into account distribution
  mechanisms for this information different from a static table.

  In order to keep the mapping rules very simple, avoiding the need to
  analyse Mail-11 addresses to distinguish the 'route', 'node', and
  Attributes (DDAs) needed to cover the mapping problem.

5.2. Mail-11 --> X.400

  We define the following Domain Defined Attributes to map a Mail-11
  address:

       DD.Dnet
       DD.Mail-11






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  We thus define the Mail-11 Phase IV mapping rule:

       route::node::localpart

     maps into

       C=xx; ADMD=yyy; PRMD=zzz; O=ooo; OU=uuu; DD.Dnet=net;
       DD.Mail-11=route::node::localpart;

  Meanwhile we define the mapping rule for Mail-11 DECnet/OSI:

       net:node-clns::localpart

     maps into

       C=xx; ADMD=yyy; PRMD=zzz; O=ooo; OU=uuu; DD.Dnet=net;
       DD.Mail-11=node-clns::localpart;

  with:

       xx  = country code of the gateway performing the conversion
       yyy = Admd of the gateway performing the conversion
       zzz = Prmd of the gateway performing the conversion
       ooo = Organisation of the gateway performing the conversion
       uuu = Org. Unit(s) of the gateway performing the conversion
       net = name of the DECnet network (e.g., OMNI, HEPnet, SPAN,...)

  ('zzz','ooo','uuu' being used or dropped appropriately in order to
  identify uniquely within the X.400 MHS the gateway performing the
  conversion).

  The following defaults also apply:

  if 'node' (or 'node-clns') is missing and we are mapping the Mail-11
  originator (From) then 'node' (or 'node-clns') defaults to the DECnet
  node name of the gateway (gwnode);

  if 'node' (or 'node-clns') is missing and we are mapping the Mail-11
  recipient (To, Cc) then 'node' (or 'node-clns') defaults to the
  DECnet node name of the 'From' address.

  if 'net' is missing, then it defaults to a value defined locally by
  the gateway: if the gateway is connected to one DECnet network only,
  then 'net' will be the name of this unique network; if the gateway is
  connected to more than one DECnet network, then the gateway will
  establish a 'first choice' DECnet network, and 'net' will default to
  this value.




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  The 'node' syntax (DECnet/OSI or Phase IV) depends on the DECnet
  protocol implemented and on the value of a system parameter (usually
  the MAIL$SYSTEM_FLAGS one) on the gateway host.

  In case 'local-part' contains 'x400-text-address' see also section
  6.4.3;

  In case 'local-part' contains 'RFC822-address' see also section
  6.4.4.

5.2.1. Examples

  Let us suppose that:

    - the DECnet network name (net) is 'OMNI';
    - the DECnet node name of the gateway (gwnode) is '.IT.DM.X4TDEC'
      alias 'X4TDEC' in Phase IV;
    - the Country Code of the gateway is 'IT' and its ADMD is 'garr'
      (and these two fields are enough to identify uniquely the gateway
      within the X.400 MHS).

   USER47
    C=it; ADMD=garr; DD.Dnet=OMNI; DD.Mail-11=.IT.DM.X4TDEC::USER47;

   MYNODE::BETTY
    C=it; ADMD=garr; DD.Dnet=OMNI; DD.Mail-11=MYNODE::BETTY;

   BOSTON::GOOFY1::MARY34
    C=it; ADMD=garr; DD.Dnet=OMNI; DD.Mail-11=BOSTON::GOOFY1::MARY34;

   .DE.UNI-BN.PHYS.NODE18::MARY34
    C=it; ADMD=garr; DD.Dnet=OMNI;
    DD.Mail-11=.DE.UNI-BN.PHYS.NODE18::MARY34;

   UCLA13::MVAX93::MRGATE::"MBOX1::MBX34:MYC3::BOB"
    C=it; ADMD=garr; DD.Dnet=OMNI;
    DD.Mail-11=UCLA13::MVAX93::MRGATE::(q)MBOX1::MBX34::MYC3::BOB(q)

   ENET:.US.CENTRAL.MIAMI2::George.Rosenthal
    C=it; ADMD=garr; DD.Dnet=ENET;
    DD.Mail-11=.US.CENTRAL.MIAMI2::George.Rosenthal;

   MRGATE::"C=xx::A=bbb::P=ppp::S=Joe"
    C=it; ADMD=garr; DD.Dnet=OMNI;
    DD.Mail-11=X4TDEC::MRGATE::(q)C=xx::A=bbb::P=ppp::S=Joe(q)






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   MAINVX::In%"path1!path2!user%dom"
    C=it; ADMD=garr; DD.Dnet=OMNI;
    DD.Mail-11=MAINVX::In(p)(q)path1(b)path2(b)user(p)dom(q)

5.3. X.400 encoding of Mail-11 --> Mail-11

  In order to assure path reversibility in case of multiple Mail-
  11/X.400 gateway crossing we must distinguish two cases:

  - DD.Dnet=net is known to the gateway as one of the DECnet networks
    it is connected to. In this case the mapping is trivial:

       C=xx; ADMD=yyy; PRMD=zzz; O=ooo; OU=uuu; DD.Dnet=net;
       DD.Mail-11=route::node::localpart;

  (see sect. 5.2 for explication of 'xx','yyy','zzz','ooo','uuu','net')

  maps into

       route::node::localpart

  and for DECnet/OSI addresses

       C=xx; ADMD=yyy; PRMD=zzz; O=ooo; OU=uuu; DD.Dnet=net;
       DD.Mail-11=node-clns::localpart;

  maps into

       net:node-clns::localpart

  - DD.Dnet=net is NOT known to the gateway as one of the DECnet
    networks it is connected to. In this case the mapping rule
    described into section 5.4 apply:

       C=xx; ADMD=yyy; PRMD=www; DD.Dnet=net;
       DD.Mail-11=route::node::localpart;

  maps into

       gwnode::gw%"C=xx;ADMD=yyy;PRMD=www;DD.Dnet=net;
       DD.Mail-11=route::node::localpart;"










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  Again for DECnet/OSI addresses:

       C=xx; ADMD=yyy; PRMD=www; DD.Dnet=net;
       DD.Mail-11=node-clns::localpart;

  maps into

       gwnode::gw%"C=xx;ADMD=yyy;PRMD=www;DD.Dnet=net;
       DD.Mail-11=node-clns::localpart;"


5.3.1. Examples

  Let us suppose that:

    - the DECnet network name (net) is 'OMNI';
    - the DECnet node name of the gateway (gwnode) is '.IT.DM.X4TDEC';
      alias 'X4TDEC' in Phase IV;
    - the Country Code of the gateway is 'IT' and its ADMD is 'garr';

    (and these two fields are enough to identify uniquely the gateway
    within the X.400 MHS).

    C=it; ADMD=garr; DD.Dnet=OMNI;
    DD.Mail-11=X4TDEC::MRGATE::(q)C=ab::A=dsa::P=qwty::OU=mie::S=Cly(q)
      MRGATE::"C=ab::A=dsa::P=qwty::OU=mie::S=Cly"

    C=it; ADMD=garr; DD.Dnet=EASYNET; DD.Mail-11=ROM01::CARLO;
      X4TDEC::gw%"C=it;ADMD=garr;DD.Dnet=EASYNET;
      DD.Mail-11=ROM01::CARLO;"

  (in the above example 'EASYNET' is supposed to be not connected to
  our gateway located on .IT.DM.X4TDEC DECnet node).

5.4. X.400 --> Mail-11

  The mapping of an X.400 O/R address into Mail-11 is done encoding the
  various attributes into the X400-text-address as defined in chapter 4
  of MIXER, and including this as 'f-address'. A 'f-pref' and a the
  DECnet node name of the gateway.











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  Thus

     x400-text-address

  will be encoded like

     gwnode::gw%"x400-text-address"

  having spaces dividing attributes as optional.

5.4.1. Example

  Let us suppose that:

    - the DECnet node name of the gateway (gwnode) is '.IT.DM.X4TDEC'
      alias 'X4TDEC' in Phase IV, and 'net' is 'OMNI'

  Thus

     C=gb; ADMD=G400; PRMD=AC.UK; O=ucl; S=Clay;

  will be encoded like

   X4TDEC::gw%"/C=gb/A=G400/P=AC.UK/O=ucl/S=Clay"

  or its equivalent with the ";" notation and DECnet/OSI 'node'

   OMNI:.IT.DM.X4TDEC::gw%"C=gb;ADMD=G400;PRMD=AC.UK;O=ucl;S=Clay;"

5.5. Mail-11 encoding of X.400 --> X.400

  It can happen that Mail-11 is used to relay messages between X.400
  systems; this will mean multiple X.400/Mail-11 gateway crossing and
  we will encounter Mail-11 addresses containing embedded X.400
  informations. In order to assure path reversibility we must then
  distinguish two cases:















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  - the embedded X.400 address belongs to a domain whose naming and
    routing rules are known to the global X.400 MHS.  In this case the
    mapping is trivial:

      route::gwnode::gw%"x400-text-address"

    or (for DECnet/OSI)

      net:gwnode::gw%"x400-text-address"

  maps into

      x400-text-address

     'route' and 'gwnode' are mapped into X.400 Trace service elements.

  - the encoded X.400 domain does not belong to the global X.400 name
    space. In this case the mapping rule described into section 5.2
    apply:

      route::gwnode::gw%"x400-text-address"

  maps into

      C=xx; ADMD=yyy; DD.Dnet=net;
      DD.Mail-11=route::gwnode::gw(p)(q)x400-text-address(q);

  and (for DECnet/OSI)

      net:gwnode::gw%"x400-text-address"

  maps into

      C=xx; ADMD=yyy; DD.Dnet=net;
      DD.Mail-11=gwnode::gw(p)(q)x400-text-address(q);

  The latter case is deprecated and must be regarded as a possible
  temporary solution only, while waiting to include into the global
  X.400 MHS also this domain.












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5.5.1. Examples

  Let us suppose that:

    - the DECnet network name (net) is 'OMNI';
    - the DECnet node name of the gateway (gwnode) is '.IT.DM.X4TDEC'
      alias 'X4TDEC' in Phase IV;
    - the Country Code of the gateway is 'IT' and its ADMD is 'garr';
      (and these two fields are enough to identify uniquely the
      gateway within the X.400 MHS).

    X4TDEC::gw%"C=fr;ADMD=atlas;PRMD=ifip;O=poly;S=Moreau;"
      C=fr; ADMD=atlas; PRMD=ifip; O=poly; S=Moreau;

    X4TDEC::gw%"C=zz;ADMD= ;PRMD=Botwa;O=Miner;S=Chiuaw;"
      C=it; ADMD=garr; DD.Dnet=OMNI;
      DD.Mail-11=X4TDEC::gw(p)(q)C=zz;ADMD= ;
      PRMD=Botwa;O=Miner;S=Chiuaw;(q)

  (in the above example  C=zz is unknown to the global X.400 MHS)

Chapter 6 - Mapping - Mail-11 / RFC822

6.1 Introduction

  The implementation of a Mail-11 - RFC822 gateway was faced by many
  software developers independently, and was included in many mail
  products which were running on both VMS and UNIX systems. As there
  was not a unique standard mapping way, the implementations resulted
  into a number of possible variant methods to map a Mail-11 address
  into an RFC822 one. Some of these products became then largely
  widespread, starting to create a number of de facto mapping methods.

  In this chapter some sort of standardisation of the mapping problem
  is considered, trying to be compatible with the existing installed
  software. We must also remind that, in some cases, only simple Mail-
  11 addresses could be mapped into RFC822, having complex ones
  producing all sort of quite strange results. In case DECnet/OSI
  Mail-11 addresses are involved we must also notice that only one
  mapping method can be used from/to RFC822 addresses.











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  On the other hand, the mapping of an RFC822 address in Mail-11 was
  quite straightforward, resulting in a common definition which uses
  "Mail-11 foreign mail protocol" to design an RFC822 address:

     [[node::][node::]...]prot%"rfc-822-address"

  or

     [node::][node::]...]prot::"rfc-822-address"

  or again for DECnet/OSI addresses

     [net:][node-clns::]prot%"rfc-822-address"

  or

     [net:][node-clns::]prot::"rfc-822-addres"

6.2 De facto implementations

  A considerable number of de-facto implementations of Mail-11/RFC822
  gateways is existing. As said in the introduction, the mapping of
  RFC822 addresses in Mail-11 is accomplished using the foreign mail
  protocol syntax and is thus unique.

  On the other hand, Mail-11 addresses are encoded in RFC822 syntax in
  various ways. Here are the most common ones:

       a) "node::user"@gateway-address
       b) user%node@gateway-address
       c) [email protected]
       d) user%node.dnet@gateway-address

Let's have a quick look to these different choices.

  a - This form simply encloses as quoted Left Hand Side string the
      original Mail-11 address into the RFC822 address of the
      Mail-11/RFC822 gateway. This method is fully conformant with
      RFC822 syntax, and the Mail-11 address is left untouched; thus
      no encoding rules need to applied to it. This method applies also
      easily to DECnet/OSI Mail-11 addresses.

  b - As one will immediately notice, this form has nothing in it
      indicating the address is a Mail-11 one; this makes the encoding
      indistinguishable from a similar encoding of RSCS (BITnet)
      addresses used by some IBM VM Mailer systems. It should thus be
      deprecated.




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  c - In this case a sort of 'reserved word' (DECnet)  embedded into
      the address itself identifies the presence of a Mail-11 original
      address preceding it. The decoding is possible, dropping
      'domains' and extracting 'user' and 'node' parts. However complex
      Mail-11 addresses cannot be mapped properly in this syntax, and
      there is no specific rule for adding the 'domains' part of the
      address.

  d - In this case again there is a 'reserved word' (dnet)  which make
      possible the identification of the original Mail-11 address;
      'gateway-address' points to the Mail-11/RFC822 gateway and 'node'
      and 'user' information can be easily drawn from the address.
      However complex Mail-11 addresses cannot be embedded easily into
      this syntax.

  Note the only methods a) can be successfully used for DECnet/OSI
  Mail-11 addresses, while the other cases are already too complex to
  encode in a unique way such addresses in RFC822.

6.3 Recommended mappings

  From the examples seen in the previous paragraphs we can derive a
  canonical form for representing the mapping between Mail-11 and
  RFC822.

6.3.1 RFC822 mapped in Mail-11

  The mapping of an RFC822 address in Mail-11 is straightforward, using
  the "Mail-11 foreign mail protocol" syntax. The two possible variants
  for Phase IV are:

     [[node::][node::]...]prot%"rfc-822-address"

  or

     [node::][node::]...]prot::"rfc-822-address"

  The equivalent two possible variants for DECnet/OSI are:

     [net:][node-clns::]prot%"rfc-822-address"

  or

     [net:][node-clns::]prot::"rfc-822-address"







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6.3.2 Mail-11 mapped in RFC822

  RFC822 foresee a canonical form for representing non-RFC822
  addresses: put the foreign address in local part (Left Hand Side,
  LHS) is a form as similar as possible to its original syntax. Thus
  the suggested mapping both for Phase IV and DECnet/OSI is:

     "Mail-11-address"@gateway-address

  This format assures also the return path via the appropriate gateway.

6.3.3 Mail-11 (foreign mail protocol) mapped in RFC822

  A Mail-11 address containing a foreign mail protocol syntax can also
  contain the percent '%' character as a separator between the foreign
  protocol name and the actual address itself. In some cases the
  address part can also be an unquoted string. Some examples:

     deliver%swan
     myprot%root.owner
     listserv%my-private.list.A1

  If these addresses are encoded into an RFC822 address using the
  "natural" method described in 6.3.2, they will result in something
  which can be easily mismatched with an address using the percent hack
  in LHS for source routing.

     "myprot%root.owner"@lohost.mydom.edu    (Mail-11 address)

     "LISTSERV%IBMB.BITnet"@bitgate.anu.edu  (% routing address)

  The percent hack is strongly deprecated, and thus should be avoided;
  the second address above shoud be expressed as:

     @bitgate.anu.edu:"[email protected]"

  However, in order to assure maximum functionality and avoid problems,
  it is recommended to encode Mail-11 addresses containing the foreign
  protocol specification in RFC822 syntax using the DD.Mail-11 and
  DD.dnet qualifiers, i.e.

     "/DD.Mail-11=myprot%root.owner/DD.dnet=OMNI"@lohost.mydom.edu

  The DD.dnet defaults as indicated in the similar cases for the Mail-
  11 / X.400 mappings. This encoding method can, of course, also be
  used to map any other Mail-11 address in RFC822, and is the only one
  which enable to specify the network name ('OMNI' in the above
  example) for DECnet Phase IV Mail-11 addresse. The method is fully



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  compatible with the results also produced by gateways following the
  MIXER specification for Mail-11 addresses encoded in X.400 and then
  translated into RFC822.

Chapter 7 - Complex mapping - X.400 / Mail-11 / RFC822

7.1. The protocol triangle

  The bilateral mappings described in chapters 5 and 6 must be extended
  in order to cover also the case in which also RFC822 addressing is
  involved, and the following triangular situation occurs:


                                  X.400
                                  /  \
                                 /    \
                                /      \
                            Mail-11----RFC822

  The X.400 - RFC822 side is fully covered by MIXER, and the previous
  chapters in this document cover the Mail-11 - X.400 side and the
  Mail-11 - RFC822 one.

7.2. RFC822 mapped in Mail-11

  The 'RFC822-address' is usually included in 'local-part' as

        route::gwnode::gw%"rfc822-address"

  or the equivalent in DECnet/OSI:

        net:gwnode::gw%"rfc822-address"

  An example in Phase IV

        NVXA23::SMTPGW::in%"[email protected]"

  and another one in DECnet/OSI

        OMNI:.FR.INET.LABOL.SMTPGW::in%"[email protected]"

7.3. Mail-11 mapped in RFC822

  There are different styles in mapping a Mail-11 address in RFC822;
  let's have a short summary of what was traditionally done in some
  implementations.





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7.3.1 Mail-11 address encoded in "Left Hand Side" (LHS) of RFC822
     address, using "%" syntax or "::" syntax

       route::node::localpart      (Phase IV)

  maps to

       localpart%node%route@gw-domains

  or

        "route::node::localpart"@gw-domains

  Again, let's consider the DECnet/OSI case:

     net:node-clns::localpart      (DECnet/OSI)

  maps to

       "net:node-clns::localpart"@gw-domains

  (note that "%" encoding does not exist for this case)

  where 'gw-domains' identify uniquely the Mail-11 / RFC822 gateway.

7.3.2 Mail-11 address maps partly to LHS and partly to 'domain' part of
     RFC822 address

       node::localpart

  maps to

       [email protected]

  note that this kind of mapping does not exists with DECnet/OSI Mail-
  11 addresses.

7.3.3 Mail-11 address is completely hidden by a mapping table

  In this case the resultant RFC822 address contains no trace at all of
  the original Mail-11 address.










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7.4. Multiple conversions

  Let us now examine briefly the possible situations which involve
  multiple conversions, having one protocol as a relay between the
  other two. This summary suggest some possible enhanced solutions to
  avoid heavy and unduly mappings, but the 'step by step' approach,
  considering blindly one conversion as disjointed to the other, as
  described in the previous sections, can always be used.

7.4.1. X.400 --> RFC822 --> Mail-11

  We apply the MIXER rules to the first step, obtaining an RFC822
  address which can be mapped in Mail-11 using the 'f-address' field,
  as described in section 7.2.

  an example:

     C=gb; ADMD=Gold 400; PRMD=AC.UK; O=UCL; OU=cs; G=Jim; S=Clay;

  maps accordingly to MIXER to

     [email protected]

  and finally becomes

     SMTPGW::In%"[email protected]"

  and finally becomes

     SMTPGW::In%"[email protected]"

  where 'SMTPGW' is the DECnet Phase IV node name of the machine
  running the RFC822 to Mail-11 gateway. Again, in case the machine
  running the RFC822 to Mail-11 gateway is a DECnet/OSI one (like
  OMNI:.US.VA.CENTRL) we would get

     OMNI:.US.VA.CENTRL::In%"[email protected]"

7.4.2. Mail-11 --> RFC822 --> X.400

  Some of the possible mapping described in section 7.3 for Phase IV
  apply to the Mail-11 address, hiding completely its origin. The MIXER
  apply on the last step.








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  an example:

     RELAY::MYNODE::BETTY

  could map into RFC822 as

     BETTY%[email protected]

  and accordingly to MIXER

     C=it; A=garr; P=dom1; O=gw1; OU=RELAY; S=BETTY(p)MYNODE;

  where 'dnet.gw1.it' is the domain of the machine running the Mail-11
  to RFC822 gateway.

7.4.3. X.400 --> Mail-11 --> RFC822

  The X.400 address is stored into Mail-11 'f-address' element as
  described in sections 5.3 and 5.4; then if the Mail-11 to RFC822
  gateway is able to understand the presence of a 'x400-text-address'
  nto the Mail-11 address, then it applies MIXER to it, and encodes
  header. Otherwise it applies the rules described in 7.3.

  an example:

    C=gb; ADMD=Gold 400; PRMD=AC.UK; O=UCL; OU=cs; G=Jim; S=Clay;

  will be encoded like

    X4TDEC::gw%"/C=gb/A=Gold 400/P=AC.UK/O=UCL/OU=cs/G=Jim/S=Clay"

  If the Mail-11 to RFC822 gateway recognise the x400-text-address,
  then the address becomes, accordingly to MIXER

    [email protected]

  and the following RFC822 header line is added

    Received: from X4TDEC with DECnet (Mail-11) on xx-xxx-xxxx.

  Otherwise one of the dumb rules could produce

   gw%"/C=gb/A=Gold 400/P=AC.UK/O=UCL/OU=cs/G=Jim/S=Clay"@X4TDEC.doms

  The case with DECnet/OSI Mail-11 is conceptually identical.






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7.4.4. RFC822 --> Mail-11 --> X.400

  The RFC822 address is encoded in Mail-11 f-address element as
  described in sect. 7.2; then if the Mail-11 to X.400 gateway is able
  to understand the presence of an 'RFC822-address' into the Mail-11
  address, then it applies MIXER to it, and encodes 'route' and applies
  the rules described in 5.2 and 5.5.

  an example:

     [email protected]

  will be encoded like

     SMTPGW::In%"[email protected]"

  If the Mail-11 to X.400 gateway recognise the RFC822-address, then
  the address becomes, accordingly to MIXER

     C=gb; ADMD=Gold 400; PRMD=AC.UK; O=UCL; OU=cs; G=Jim; S=Clay;

  and a 'trace' record is added into the X.400 P1 data, stating that a
  node named SMTPGW was crossed.

  Otherwise dumb rule produces

     C=it; ADMD=garr; DD.Dnet=HEP;
     DD.Mail-11=SMTPGW::In(p)(q)Jim.Clay(a)cs.UCL.AC.UK(q)

  Again, the case for DECnet/OSI Mail-11 addresses, is conceptually
  identical.

7.4.5. RFC822 --> X.400 --> Mail-11

  We apply MIXER to the first conversion, obtaining an X.400 address.
  Then the rules described in sections 5.3 and 5.4 are used to store
  the X.400 address as 'x400-text-address' into the Mail-11.














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  an example:

     [email protected]

  maps accordingly to MIXER to

     C=gb; ADMD=Gold 400; PRMD=AC.UK; O=UCL; OU=cs; G=Jim; S=Clay;

  and finally becomes

     SMTPGW::gw%"/C=gb/A=Gold 400/P=AC.UK/O=UCL/OU=cs/G=Jim/S=Clay"

  where 'SMTPGW' is the DECnet Phase IV node name of the machine
  running the X.400 to Mail-11 gateway. No differences also for
  DECnet/OSI Mail-11 addresses.

7.4.6. Mail-11 --> X.400 --> RFC822

  The Mail-11 address is encoded as specified in sections 5.2 and 5.5;
  then MIXER is used to convert the address in RFC822.

  an example:

     RELAY::MYNODE::BETTY

  maps into X.400 as

     C=it; ADMD=garr; DD.Dnet=OMNI; DD.Mail-11=RELAY::MYNODE::BETTY;

  and accordingly to MIXER

     "/C=it/A=garr/DD.Dnet=OMNI/DD.Mail-11=RELAY::MYNODE::BETTY"@gw2.it

  where 'gw2.it' is the domain of the machine running the MIXER
  gateway.

7.4. Conclusions

  A standard way of mapping Mail-11 addresses into RFC822 and vice
  versa is feasible. A suggestion is thus made to unify all existing
  and future implementations. It should be noted, however, that it
  could be impossible (in case of DECnet Phase IV) to specify in these
  mappings the name of the decnet community owning the encoded address,
  as it can be always done for X.400; thus the implementation of the
  'intelligent' gateway in this case could result impossible.






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Chapter 8 - Notifications and Probes

8.1. Overview

  Mail-11 is a real time protocol, i.e. connection is established
  directly to the destination node. This makes possible some level of
  services like verification of an address, and delivery confirmation.

  However, Mail-11 User Agents ususally do not support notification or
  probe services, whereas it is possible to deliver the result of a
  notification or a probe to Mail-11. In this section we will briefly
  describe the level of service which can be obtained on these services
  when Mail-11 is involved.

8.2. Delivery of Notifications via Mail-11

  As described in the previous chapters, it is possible to transport
  also in Mail-11 with minimal loss of information complex information.
  This also includes Notifications. In fact Notifications in
  RFC822/MIME are encoded as MIME multipart messages: there are thus no
  problems in transporting these messages in Mail-11 as any other MIME
  message. Also X.400 Notifications can be transported and delivered
  via Mail-11: MIXER describes in fact how to convert them into MIME
  multipart messages, taking the problem back to the previous
  situation.

  Even when Mail-11 is just an intermediate step for a Notification
  message, this consideration just enable support for the service.

8.3. Generation of Notifications and Probes from Mail-11

  Although Mail-11 does not support Notification or Probe, the service
  could also be supported at gateway level. In fact, due to real time
  nature of Mail-11 protocol, the gateway could be reasonably sure that
  delivery until the other end of the Mail-11 path was successful or
  unsuccessful (and try to verify the feasibility of a delivery in case
  a Probe as requested). However, Mail-11 could just be an intermediate
  relay service, vanishing the value of the information.

  Implementation of this kind of service at gateway level is thus
  questionable, and if done, should clearly state the situation where
  it was generated, and the "confidence level" it conveys.

Security Considerations

  Security issues are not discussed in this memo.





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Acknowledgements

  I wish to thank all those people who read the first draft and
  contributed a lot with their useful suggestions to the revision of
  this document, in particular RARE WG1 and IETF X.400 ops group
  members and S. E. Kille.

  Thanks also to a number of implementors (among which Ned Freed,
  Julian Onions, The Hebrew University of Tel Aviv - Pine VMS support
  team), to the HEPnet Mail Technical Committee and to all my Mail-11
  "end users", in particular Enzo Valente, for their suggestions and
  wishes which helped me really a lot to prepare this revision of
  former RFC1405.

References

  [1]  CCITT, "CCITT Recommendations X.400-X.430", Message Handling
       Systems: Red Book, October 1984.

  [2]  CCITT, "CCITT Recommendations X.400-X.420", Message Handling
       Systems: Blue Book, November 1988.

  [3]  CCITT/ISO, "CCITT Recommendations X.400/ ISO IS 10021-1,"
       Message Handling: System and Service Overview , December 1992.

  [4]  Crocker D., "Standard of the Format of ARPA Internet Text
       Messages", STD 11, RFC 822, UDel, August 1982.

  [5]  Kille, S., "MIXER (Mime Internet X.400 Enhanced Relay):
       Mapping between X.400 and RFC 822/MIME", RFC 2156, January
       1998.

  [6]  Alvestrand H., Kille S., Miles R., Rose M., and Thompson S.,
       (MIME-MHS) "Mapping between X.400 and RFC-822 Message Bodies,"
       RFC 1495, Aug 1993.

  [7]  Digital Equipment Corp., "VMS Mail Utility".

  [8]  Joiner Associates Inc., "Jnet User's Manual".

  [9]  PMDF User's Guide.

  [10] Alvestrand, H. "Writing X.400 O/R Names", UNINETT / RFC1685,
       August 1994.

  [11] CCITT, "F.401 CCITT Message Handling Services - Operations and
       Definitions of Service - Naming and Addressing for Public
       Message Handling Services, Annex B (08/92)", August 1992.



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Author's Address

  Claudio Allocchio
  Sincrotrone Trieste
  SS 14 Km 163.5 Basovizza
  I 34012 Trieste
  Italy

  Phone:   +39 40 3758523
  Fax:     +39 40 3758565
  EMail:  [email protected]
          C=it; A=garr; P=Trieste; O=Elettra; S=Allocchio; G=Claudio;







































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Full Copyright Statement

  Copyright (C) The Internet Society (1998).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
























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