Now, this is interesting: the IETF Sender ID working group is apparently defunct. This is more or less the equivalent of that milestone of farce comedies, the divorce due to irreconcilable differences.
The MARID working group was charged with adopting a standard, but factions within the working group were unable to reach agreement on whether Sender ID should be that standard. That’s because Microsoft holds some key patents on Sender ID components, and the IETF generally doesn’t want to see patented technologies enshrined as IETF standards. That’s a laudable goal, but unfortunately it’s torpedoed the adoption of SPF or Sender ID at this point. We’ll have to wait and see what happens, and whether any vendors sign on to Sender ID despite the unlikelihood of it ever becoming an IETF standard.
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