Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321

Dave Crocker <> Sun, 04 October 2020 18:35 UTC

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To: Keith Moore <>
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From: Dave Crocker <>
Organization: Brandenburg InternetWorking
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Date: Sun, 4 Oct 2020 11:35:20 -0700
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Subject: Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
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On 10/4/2020 11:28 AM, Keith Moore wrote:
> On 10/4/20 2:19 PM, Dave Crocker wrote:
> It's easy to find documentation about how highways are engineered to 
> permit safe operation at certain speeds (slightly greater than statutory 
> speed limits), also taking into account road conditions, traffic volume, 
> etc.   The "expectation" you refer to is not merely an informal 
> convention, it's a result of explicit design.

Actually, it has little or nothing to do with road engineering. 
Objectively, in fact, anything over about 55 mph is extremely unsafe, 
given typical human reaction behaviors, at the list.

So this is primarily a matter of operating convention by the folk who 
police the roads.  Unwritten but highly reliable.  Except when it isn't.

> But I'm not your trained monkey, and I'm not bound to jump through 
> whatever arbitrary hoops you hold up,so you can Google that for 
> yourself.   I suspect that you don't actually care, you're just trying 
> to insult me again.

Keith, the above is pure ad hominem.  That violates IETF rules.

It would be nice to see those rules enforced.  The failure is also a 
matter of convention that violators rely on.  Quite successfully.

Dave Crocker
Brandenburg InternetWorking