Appendix A. Internet RFCs Relating to Email

This list of Internet Request for Comments includes RFCs of several types: standards, proposed standards, experimental, informational, historical, and even humorous. The type is not listed here but should be checked before being implemented. All RFCs may be obtained via the World Wide Web at the Ohio State University RFC repository (

Full bibliographically correct references (including authors’ names) are available from the Ohio State URL. They are not included here in order to facilitate quick scanning of the available RFCs.

An attempt has been made to reduce the mail-related RFCs to those that remain useful. A full list of all Internet mail-related RFCs would include many that are formally obsolete or overcome by events. Those have been deleted from this list. Those that remain should be valid and useful for some time to come. New RFCs will be listed on the Ohio State URL when they become available.

Some of the RFCs listed have peripheral utility for mail system implementors. The basic LDAP RFCs, for example, are included because some modern MUAs have implemented address lookups via LDAP. Most of those listed, however, relate directly to electronic mail.

RFC Number


RFC 2440

OpenPGP Message Format

RFC 2425

MIME Content-Type for Directory Information

RFC 2426

vCard MIME Directory Profile

RFC 2305

A Simple Mode of Facsimile Using Internet Mail

RFC 2304

Minimal FAX Address Format in Internet ...

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