EMA MAWG FTBP Profile

X.420 (1988) defined a number of bodypart types that could be used to attach files to a message. These included:

• bilaterally-defined
• nationally-defined
• externally-defined

However, none of these bodyparts types was suitable for supporting the wide range of document types that existed. There was no agreed way to carry information about the file, for example, the filename (including extension), the file type, creation date, beyond the actual binary content of the file itself.

In 1992 the File Transfer Bodypart (FTBP) was introduced which provided a specific way to carry file attachments which also included a wide variety of information about the file itself. However, with so many new fields interoperability of FTBP was likely to become and issue and in particular, there was no agreed definition of some of the more common attachment types.

Recognising this as an issue, the Electronic Mail Association (EMA) (now part of The Open Group) formed the Message Attachment Working Group (MAWG) to produce a FTBP Profile that would support interoperability between implementations. Working with the main messaging vendors of the day, including current SMHS staff, a profile was generated that specifies both

• the fields an client must originate and receive and
• the definitions (OIDs) for the common file types.

The profile has been widely adopted and greatly increased interoperability between vendors and as such is usually a requirement for any X.400 messaging solution.

The profile has also been adopted in RFC 2157 - Mapping between X.400 and RFC 822/MIME Message Bodies which describes how to map body parts of X.400 messages into MIME entities and vice versa, including the handling of multipart messages and forwarded messages.

Version 1.5.1 of the profile can be downloaded here.