http://www.ietf.org/rfc/rfc1767.txt
Electronic Data Interchange (EDI) provides a means of conducting structured transactions between trading partners. The delivery mechanism for these types of transactions in a paper world has been the postal system, so it is to be expected that electronic mail would serve as a natural delivery mechanism for electronic transactions. This specification permits formatted electronic business interchanges to be encapsulated within MIME messages [Bore92]. For the specification effort, the basic building block from EDI is an interchange.

This specification pertains only to the encapsulation of EDI objects within the MIME environment. It intends no changes in those objects from the primary specifications that define the syntax and semantics of them. EDI transactions take place through a variety of carriage and exchange mechanisms. This specification adds to that repertoire, by permitting convenient carriage through Internet email.