[mail-vet-discuss] Discussion of auth-header draft (fwd)

[SM]

At 17:17 08-10-2008, Michael Thomas wrote:
>This sort of gets to the heart of a concern I've had for a long
>time about ar. Just who exactly is the consumer of an ar header?
>For me, the consumer has been either me or some automaton that
>digests the ar and produces statistics, or takes some action
>based on the digested bits. My assumption has always been that
>ar's are protected by firewall-y-like mechanisms (eg, ingress
>filtering by border mta's) and that that's good enough security.

The Authentication-results header came up during the discussion about 
DomainKeys as there was a need for a mechanism to pass the results of 
the verification.  The results can be used by downstream filters or 
MUAs which support it.  It wasn't much of a security risk as  the MTA 
inserting that header would remove any previous occurrence of the header.

>Admittedly, those are a lot of assumptions. If people are planning
>on using ar for very different uses -- especially across internally 
>secured areas, then the current design is woefully lacking. If
>they aren't then it's probably ok.

As the draft progressed, other uses were added.  One of the 
constraints was how to pass information without running into 
deployment issues and the design reflects that.

Regards,
-sm