MARID was an IETF working group in the applications area tasked to propose standards for email authentication in 2004. The name is an acronym of M<small>TA</small> Authorization Records In D<small>NS</small>.

Background

Lightweight MTA Authentication Protocol (LMAP) was a generic name for a set of 'designated sender' proposals that were discussed in the ASRG in the Fall of 2003, including:

  • Designated Mailers Protocol (DMP)
  • Designated Relays Inquiry Protocol (DRIP)
  • Flexible Sender Validation (FSV)
  • MTAMARK
  • Reverse MX (RMX)
  • Sender Policy Framework (SPF)

These schemes attempt to list the valid IP addresses that can send mail for a domain. The "lightweight" in LMAP essentially stands for "no crypto", as opposed to DomainKeys and its successor, DKIM. In March 2004, the Internet Engineering Task Force IETF held a <span title="Birds of a Feather">BoF</span> on these proposals. As the result of that meeting, the task force chartered the MARID working group.

Controversy

Microsoft's Caller-ID proposal was a late and highly controversial addition to this mix. It came with the following features:

  • Use of XML policies with DNS - this was reduced to what is now known as Sender ID
  • Piggybacking and extension of the existing SPF
  • Use of RFC 2822 mail header fields as by DomainKeys (All other LMAP drafts used the SMTP envelope.)
  • Specific questions about patents and licensing

The responsible IETF Area Director agreed to sponsor the publication of some of the unfinished MARID discussions as IETF experiments; these happened in 2005, as both the pre-MARID SPF and Sender ID were approved as experimental RFCs. The latter is to a certain degree a result of MARID, growing out of the Caller-ID proposal.

The ongoing disputes on technical issues and incompatibilities in Sender ID resulted later in appeals to the IESG and the IAB.

References

  • Historical ASRG LMAP draft (2004)
  • MARID status page (2004) and mxcomp list archive
  • IESG applications area DEA directorate (dissolved)
  • IAB appeal with links to more sources (2006)
  • SenderID appeal history (2006)