Dave Crocker wrote:
John Levine wrote:
Under the current setup, any domain that has an A record is presumed
to be a mail domain, and if it's not, there's no good way to advertise
that fact.
Getting rid of the AAAA fallback flips the default to be in line with
reality
Flipping any 20-year default for an global installed base should be
pursued with an assumption that it won't work, not that it will. This
puts the burden of making the case on those lobbying for the change.
And it should make the barrier for adoption be pretty high. In other
words, the case needs to be compelling, not merely appealing.
20-year default for AAAA fallback?
Actually, I have the opposite question: Is _adding_ AAAA fallback in
2821bis more likely to set it back in terms of progression on standards
track? 2821 doesn't have a requirement for AAAA fallback, so it seems
that adding that requirement might be just the type of "mission creep"
you're trying to avoid.
But I'm definitely not an expert on what is and what isn't allowable in
standards track progression...
-Jim