1368 straw-poll : (was: Re: [ietf-dkim] Deployment Non-Scenario 7: Cryptographic Upgrade and Downgrade Attacks)

[Arvel Hathcock]

 > This protection depends upon a means for the signer to assert which
 > algorithm is deprecated, and what shiny new algorithm is being
 > offered.

That doesn't follow at all.  The *receiver* will decide what algorithms 
are and are not sufficient and when to act on that decision.  And 
besides, the means by which a *sender* can assert which algorithm they 
like is to just stop signing with the one(s) they don't.  Whether and 
when to do that is a decision the sender will have to make.  I don't see 
how policy plays a role in any of this.

I'm starting to think that I'm completely missing something fundamental. 
  I might need some education in Prague if folk have time.

Arvel