Thanks. It's looking like MON and MRN are the terms to use.
Probably not, since the use of multiple terms creates an architectural
separation of authority that is not reflected in real life.
An administrative authority is cohesive, whether it only sends, only received,
or both sends and receives. The purpose of the construct is to focus on the
administrative cohesiveness, not to case-analyze various sub-type of "services"
that can be performed by different, cohesive services.
The functional components (eg, MSA, mediator, MTA, etc.) reflect the role
differences just fine. There is no need to try to propagate those functional
distinctions onto the authority construct.
The ultimate example of the problem in trying to define two terms for the
authority construct arises with a mailing list, which both sends and receives.
After further discussions, I'm leaning towards the term Administrative
Management Domain (AdMD), deriving it from X.400, but with some differences in
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