An inter-MTA protocol has to be able to accept email from a
total stranger,
that's a policy directive, not a technical requirement.
Just to hammer this home, the language was "be able to". That's a
technical requirement.
The ability to exchange mail, without prior arrangement, is fundamental
to Internet mail. That a receiver might invoke policies to the contrary
is entirely their right. But the basis for the design choices of the
standards is quite clear.
d/
--
Dave Crocker
Brandenburg InternetWorking
<http://bbiw.net>
_______________________________________________
Asrg mailing list
Asrg(_at_)ietf(_dot_)org
https://www1.ietf.org/mailman/listinfo/asrg