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

Dave Crocker <dhc@dcrocker.net> Sun, 27 September 2020 16:31 UTC

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To: Keith Moore <moore@network-heretics.com>, John R Levine <johnl@taugh.com>, ietf-smtp@ietf.org
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From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Sun, 27 Sep 2020 09:31:41 -0700
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Subject: Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
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On 9/27/2020 8:43 AM, Keith Moore wrote:
>> No, we've observed in practice that hosts that don't have matching 
>> PTRs are spambots.
>
> I don't believe that anyone takes enough time to look at a sufficient 
> volume of email, often enough, to be sure of that. And again, it's a 
> self-fulfilling belief. 

Keith,

Exactly how much experience do you have with the real-world practices of 
the real-world anti-abuse industry?

I'm asking not as an ad hominem, but in order to try to find out how 
your blanket rejection can be so wildly different from what I see within 
M3AAWG.  For many years.

d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net

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