[ietf-dkim] Are subdomains like parent domains?

[Jim Fenton]

John Levine wrote:
>>> But I have to say, without any sort of domain blanket/coverage
>>> option, it seems like something is really missing here.
>>>       
>
> I'm seeing an implicit assumption that if someone has an opinion about
> mail from foo.com, they will have a similar opinion of mail from
> subdomains a.foo.com or a.b.foo.com, or a.b.c.foo.com.  I've been
> thinking about the mail I actually see, and I am having great
> difficulty finding even a small set of real life scenarios where that
> is true.
>   

When you refer to "an opinion" it sounds like you're referring to some 
sort of reputation or other state information being maintained for each 
domain.  We have been trying to make DKIM free of such dependencies.  I 
fully expect that reputations, opinions, and accreditations will often 
be used in the big-picture evaluation of email, but DKIM/ADSP should be 
an input to that process, not dependent on it.

-Jim