There isn't. We host mail for numerous domains, but we're planning to
sign all of it as d=assessment.aol.com for the reasons Suresh mentioned
(same use policies, filtering, etc.). Plus, a single user identity in my
system can have multiple email addresses associated with it, so it makes
more sense (in my mind at least) to set
i=user_id(_at_)assessment(_dot_)example(_dot_)com
instead of i=email_alias(_at_)assessment(_dot_)example(_dot_)com(_dot_) For
example, a single
dial-up customer can have up to seven mailboxes at a time but there's
still only one responsible identity for the account. I believe broadband
access providers have similar setups.
This looks just fine to me. By using the user_id, you're satisfying the
semantics of
Identity of the user or agent (e.g., a mailing list manager) on
behalf of which this message is signed
and still maintains the uniqueness of that identity.
I don't think this is the same as what Suresh was describing, though. He
was talking about using assessment labels for the i= value, such as
good(_at_)assessment(_dot_)aol(_dot_)com, rather than a value directly linked
to the
known user/agent.
Tony Hansen
tony(_at_)att(_dot_)com
And in all fairness to Suresh, I probably did initially describe the
idea to him as using i= for the assessment at some meeting in the last
year or so, but have since changed my mind on the implementation details.
_______________________________________________
NOTE WELL: This list operates according to
http://mipassoc.org/dkim/ietf-list-rules.html