Re: [ietf-smtp] [Emailcore] Proposed ESMTP keyword RCPTLIMIT

Jeremy Harris <jgh@wizmail.org> Mon, 19 April 2021 22:29 UTC

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From: Jeremy Harris <jgh@wizmail.org>
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Date: Mon, 19 Apr 2021 23:29:29 +0100
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Subject: Re: [ietf-smtp] [Emailcore] Proposed ESMTP keyword RCPTLIMIT
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On 19/04/2021 22:18, Ned Freed wrote:
> Are there any additional limits you think are sufficiently
> important, and perhaps more to the point, in some sense foundational, that they
> warrant being in the base specification?

Just came to mind: a limit on concurrent connections. By server IP seems
most obvious, but perhaps by recipient domain might be wanted in some
cases?

> I'm especially interested in people's thoughts on rate limits.

Much harder to define and handle than the limits so far defined.
I'd prefer to leave any such for a later spec.
-- 
Cheers,
   Jeremy