Just for the sake of trying to cover all the bases:
Are there any easily-adopted (or adapted) methods we could at least
reference to cover the area of auto-configuration, such as secure
discovery of which MTAs are considered "internal" in the context of
Authentication-Results?
DHCP comes to mind but I don't think it includes provisions for
discovery of inbound or internal MTAs, or what authserv-ids they might use.
What about LDAP?
Something else?
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