On December 15, 2021 4:16:13 AM UTC, Douglas Foster <dougfoster.emailstanda...@gmail.com> wrote: >What does we mean for an RFC5322.From address to be “non-existent”? > >We have said that it is non-existent because it fails the MX/A/AAAA test, >but we have not documented what that test represents. Perhaps it seemed >obvious, but let's make it clear: > >A failed MX/A/AAAA test is a very reliable indicator that the From address >does not have a mailbox, because the associated domain does not have a mail >server which accepts messages. “Does not exist” means that the message >does not exist as a destination mailbox. > >But is that result information useful, and if so, how? What problem does >it resolve? > >I estimate that 70% of the legitimate mail entering my organization is >unidirectional – messages which do not expect a reply by email. >Unidirectional traffic does not require an inbox. When we determine that a >message does not have an inbox, we determine that it is definitely part of >the 70%. I don't find anything actionable in that information. > >The RFC5322.From identifier is an abstraction which represents a message >stream from a single entity acting as author. Everything that the author >mails can be done through agents, where the agent is the SMTP From >address. A review of actual mail messages will show that legitimate >messages come from domains that do not have a mail server. > >In the general case, an author account or domain exists simply because the >domain owner (or PSD) authorizes someone or something to use that name. >Our goal needs to be a test which identifies domain names which have never >been authorized by the domain owner or PSD. We need a different test.
None of that is at all related to why we added the np= tag. I'd suggest a review of the WG archives might be useful. Scott K _______________________________________________ dmarc mailing list dmarc@ietf.org https://www.ietf.org/mailman/listinfo/dmarc
