Damon.Sauer:> How are you going to confirm that the peer MTA is who they
say they are
if both of them are spammers and both use 0/0?
Rhetorical question... because the answer is: You can't.
We don't need to. We need to know that the domain has authorised the MTA to
transmit mail (or not). As a handy side-effect, if the domain authorises
every IP, (or a lot of IPs) that tells you something about the domain.
Every night before you go to sleep, say to yourself "MARID doesn't stop
spam and MARID doesn't stop spoofing, although it will help me detect spam
& spoofed mail". Say it 10 times. After a week, come back and re-read this
thread.