On Fri, May 23, 2025 at 01:11:52AM -0700, Chris via mailop wrote: > On 2025-05-22 20:56, Marco Moock via mailop wrote: > > On 22.05.2025 15:47 Bill Cole via mailop wrote: > > > > > For implicit TLS (as on ports 443, 465, 587, 993, 995) > > > > 587 does not use implicit TLS, it can use STARTTLS optional. > > Umm. That *may/can* be true. But as a rule it's chosen specifically > for use with TLS. I just performed a check to see if we've overlooked > anything using 587 and it's appears others have the same understanding.
The same *mis*understanding, perhaps. > Cloudflare, for example: > ---QUOTE > Originally, the Simple Mail Transfer Protocol (SMTP) used port 25. > Today, SMTP should instead use port 587 — this is the port for encrypted > email transmissions using SMTP Secure (SMTPS). That is quite an amazingly high density of wrongness. In any event, the IANA Service Name and Transport Protocol Port Number Registry, for the "submission" protocol, https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=submission, and the RFCs referenced thereby, fairly emphatically disagree with your assertion. - Matt _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
