On Tuesday, December 21, 2021 2:32:12 PM EST John Levine wrote: > It appears that Scott Kitterman <[email protected]> said: > >>> What definition are you wondering why we didn't stick to? > >> > >>Real non-existence. I'm not sure how to define it formally, ... > > The DNS has had a formal definition of non-existence for over 30 > years. You look up a name, if it returns records or NOERROR it exists, > if it returns NXDOMAIN it doesn't. There is no reason for us to invent > something new and incompatible. > > >I don't remember exactly why we settled on A/ AAAA/ MX, but the lack of a > >clear, actionable definition is why we included one. > See above. I don't remember where the text in A.4 came from, but it is > wrong. If we are telling people to test whether a domain exists, they > should do it the way the DNS does it. The correct test happens to be > cheaper than A.4, one query rather than three.
Fair enough. I can't remember why we thought RFC 8020[1] wasn't adequate when we did RFC 9091. I think we should modify the DMARC text to just refer to it. Scott K [1] https://www.rfc-editor.org/rfc/rfc8020.txt _______________________________________________ dmarc mailing list [email protected] https://www.ietf.org/mailman/listinfo/dmarc
