In article <553d43c8d961c14bb27c614ac48fc03128116...@umechpa7d.easf.csd.disa.mil> you write: >Section 2.7. defines a non-existent domain as "a domain for which there is an >NXDOMAIN or NODATA response for A, AAAA, and MX >records. This is a broader definition than that in NXDOMAIN [RFC8020]." This >should be sufficient for determining that the >domain is not intended to be used and therefore could have a more stringent >policy applied. > >The idea of looking for a "mail-enabled domain" based on if an "MX record >exists or SPF policy exists" is interesting. >Although there may be domains that send email but not receive email and so may >not have an MX record.
These days I think you will find that if the domains in your bounce address and your From: headers don't have an MX or A record, very few recipients will accept your mail. This seems like an edge case. In practice I find that the domains caught by the Org domain or I suppose PSD have A records but no mail server because they're actually web hosts rather than mail hosts. We have the Null MX to indicate that a domain receives no mail and SPF plain -all to indicate that it sends no mail so I hope we don't try to reinvent these particular wheels. R's, John _______________________________________________ dmarc mailing list dmarc@ietf.org https://www.ietf.org/mailman/listinfo/dmarc
