Greg Troxel wrote in <rmicz0447rt....@s1.lexort.com>: |Taylor R Campbell <campbell+netbsd-tech-userle...@mumble.net> writes: | |> `smtp(s)' and `submission(s)' are subtly different protocols and |> should not be aliases: |> |> - smtp(s) is for MTA<->MTA exchange of fully formed internet mail |> messages with complete headers.
Hm, but especially :25 was traditionally used by MUAs, no? Who used the submission port ~a decade ago? (I cannot truly tell about a survey though, here all was TLS, "always".) |> - submission(s) is for an MUA to submit new messages, which may not |> have complete headers or fully qualified addresses or otherwise be |> fully formed, via a mail submission agent into the internet mail |> system. | |Yes, they are different, however my take from reading |https://datatracker.ietf.org/doc/html/rfc8314 is that the orignal label |of 465 as smtps was confused, and that IANA now labels 465 as start | |> I'm also not sure it matters if a TLS session is preceded by the ten |> bytes `STARTTLS\r\n' on the wire or not. 'Had to read the RFC how that interferes with EHLO reset. |It very clearly does not matter. I think the concern was |implementations that treated TLS as optional and would continue. But |that's all rationale for why RFC8314 recommends as it does. Where we |are now is that 465/tcp is submissions and 587 is submission. And our |services file has smtps for 465, but that no longer exists in IANA-land. | |> I'm not sure if there is any port number that can rightly be called |> `smtps' today. | |Agreed. I know of no usage that is MUA-to-MUA SMTP over prenegotiated |TLS. It's basically a STARTTLS over 25 world -- which is what I think |you are thinkig | |For this thread, I think all that matters is that we find a reasonable |way to update services to match IANA while maintaining local diffs. We |have gotten into a bad state. --End of <rmicz0447rt....@s1.lexort.com> --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
