Network Working Group                                    H. Alvestrand
Request for Comments: 2158                                     UNINETT
Category: Standards Track                                 January 1998


                         X.400 Image Body Parts

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 (1998).  All Rights Reserved.

1.  Introduction

   This document contains the body parts defined in RFC 1495 for
   carrying image formats that were originally defined in MIME through
   an X.400 system.

   It also documents the OIDs assigned to these data formats as FTAM
   body parts, which allow the MIME types to be converted to FTAM body
   parts; this will probably be more useful than the new body parts
   defined here.

2.  Newly defined X.400 body parts

2.1.  The JPEG body part

   The following Extended Body Part is defined for JPEG data streams.
   It has no parameters.

       jpeg-body-part EXTENDED-BODY-PART-TYPE
         DATA            OCTET STRING
         ::= mime-jpeg-body

       mime-jpeg-body OBJECT IDENTIFIER ::=
               { mixer-bp-data 3 }

   The content is as defined in [MIME].

2.2.  The GIF body part

   The following Extended Body Part is defined for GIF data streams.  It
   has no parameters.

       gif-body-part EXTENDED-BODY-PART-TYPE
         DATA            OCTET STRING
         ::= mime-gif-body

       mime-gif-body OBJECT IDENTIFIER ::=
               { mixer-bp-data 4 }

   The content is as defined in [MIME].

3.  Defined equivalences with MIME types

3.1.  image/jpeg - jpeg-body-part

   X.400 Body Part: Extended Body Part, OID jpeg-body-part
   MIME Content-Type: image/jpeg
   Conversion: None

3.2.  image/jpeg - FTAM EMA JPEG

   X.400 Body Part: FTAM EMA JPEG
   MIME Content-Type: image/jpeg
   Conversion: None

   The OID assigned to JPEG by EMA in [MAWG] is

   { ema objects(2) messaging (2) attachments(1) jpeg-image(6) }

   while EMA's OID is

   { joint-iso-ccitt(2) country(16) us(840) organization(1)
   ema(113694) }

   making the total OID, numeric only

   { 2 16 840 1 113694 2 2 1 6 }

3.3.  image/gif - gif-body-part

   X.400 Body Part: Extended Body Part, OID gif-body-part
   MIME Content-Type: image/gif
   Conversion: None

3.4.  image/gif - FTAM EMA GIF

   X.400 Body Part: FTAM EMA GIF
   MIME Content-Type: image/jpeg
   Conversion: None

   The OID assigned to JPEG by EMA in [MAWG] is

   { ema objects(2) messaging (2) attachments(1) gif-image(4) }

4.  Security Considerations

   Security issues are not considered in this memo.

5.  References

   [MIME]
       Freed, N., and N. Borenstein, "Multipurpose Internet Mail
       Extensions (MIME) Part One: Format of Internet Message Bodies",
       RFC 2045, November 1996.

   [MAWG]
       Electronic Messaging Association Message Attachment Working Group
       (MAWG): File Transfer Body Part Feasibility Project Guide -
       version 1.5.1 - March 1996.

6.  Author's Address

   Harald Tveit Alvestrand
   UNINETT
   Postboks 6883 Elgeseter
   N-7002 TRONDHEIM

   Phone: +47 73 59 70 94
   EMail: Harald.T.Alvestrand@uninett.no

7.  Full Copyright Statement

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

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   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
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   developing Internet standards in which case the procedures for
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   The limited permissions granted above are perpetual and will not be
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   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
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