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Re: [ietf-smtp] CHUNKING and PIPELINING

Tony Finch <dot@dotat.at> Sat, 13 March 2021 00:30 UTC

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Date: Sat, 13 Mar 2021 00:30:21 +0000
From: Tony Finch <dot@dotat.at>
To: ietf-smtp@ietf.org
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Subject: Re: [ietf-smtp] CHUNKING and PIPELINING
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Viktor Dukhovni <ietf-dane@dukhovni.org> wrote:
>
> So indeed you can pipeling the entire MAIL transaction from "MAIL"
> to "QUIT" (if the number of BDAT segments is small enough).
>
> What's worse (or better depending on your perspective) is that
> you can even pipeline MULTIPLE mail transactions, nothing there
> to stop the next "MAIL" command being sent right after "BDAT LAST".
>
> At some point a 3030bis clarifying these issues would be welcome
> IMHO.

This reminds me of 2007 when I was writing various speculative drafts
http://fanf2.user.srcf.net/hermes/doc/qsmtp/ about reducing SMTP
submission latency, and the question of freely pipelining multiple
transactions came up back then. I don't think there was enough BDAT in the
wild for it to be a pressing concern, so the ideas never went anywhere.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  https://dotat.at/
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