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

John Levine <johnl@taugh.com> Sun, 26 April 2020 20:37 UTC

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Date: 26 Apr 2020 16:37:19 -0400
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From: "John Levine" <johnl@taugh.com>
To: ietf-smtp@ietf.org
Cc: ned.freed@mrochek.com
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Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf-smtp/AJDLyFTFcHvuqkTQEQw58FTanyM>
Subject: Re: [ietf-smtp] MTA-MTA SMTP and TLS-on-connect
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In article <01RK5KUREEZA000058@mauve.mrochek.com> you write:
>> should we think about technical means to facilitate the latter?
>
>Absolutely not. Relaying mail is complicated enough already; adding another
>port and DNS lookup to the mix and all the associated failure modes consistutes
>a huge cost with no real benefit.

Agreed, the extra overhead of HELO and STARTTLS is not important, and the net is
already overoptimized for mail on port 25.

I am reasonably sure that if we didn't already have port 465 in
addition to 587, nobody would invent it.

-- 
Regards,
John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly