Re: [ietf-smtp] MTA-MTA SMTP and TLS-on-connect

John Levine <johnl@taugh.com> Sun, 26 April 2020 22:20 UTC

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From: "John Levine" <johnl@taugh.com>
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Subject: Re: [ietf-smtp] MTA-MTA SMTP and TLS-on-connect
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In article <8d3d7446-db7d-ac04-2a36-258643254630@wizmail.org> you write:
>Hi,
>
>Noting that https://tools.ietf.org/html/draft-sheffer-uta-rfc7525bis-00
>section 3.2 says that TLS-on-connect SHOULD be preferred over STARTTLS
>(my rephrasing) - and that while T-o-c is reasonably common for MSA-MTA
>but not for MTA-MTA -
>
>should we think about technical means to facilitate the latter?

Turns out the STARTTLS language was in RFC 7525 and we missed it.

If this draft goes anywhere, I think we should tell them to fix it and
say that STARTTLS and TLS-on-connect are equivalent if the path with
STARTTLS requires its use, which I think reflects reality.

R's,
John