Re: [dmarc-ietf] Ticket #11 (and #112) - Proposed language

Alessandro Vesely <vesely@tana.it> Wed, 16 June 2021 17:51 UTC

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To: John Levine <johnl@taugh.com>, dmarc@ietf.org
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From: Alessandro Vesely <vesely@tana.it>
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Date: Wed, 16 Jun 2021 19:51:09 +0200
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Subject: Re: [dmarc-ietf] Ticket #11 (and #112) - Proposed language
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On Wed 16/Jun/2021 18:01:08 +0200 John Levine wrote:
> It appears that Alessandro Vesely  <vesely@tana.it> said:
>>However, to reject based just on NXDOMAIN is too harsh.
> 
> I dunno, in my experience it's quite common, and if you do, the chances of losing a message you care
> about are negligible.


It's been customary to reject NXDOMAIN in smtp.mailfrom since when I recall it. 
  To reject NXDOMAIN in header.from is (was) an ADSP feature which doesn't seem 
to be very widespread.  DMARC dropped it a long time ago.


> In any event, this has nothing to do with DMARC.  If for some reason you want to do a DMARC evaluation
> of a non-existent domain, you can use the organizational domain or I suppose PSD.


It might make sense to reject that ~30% which doesn't even have an 
organizational domain (dubbed totally astray in my previous post).  But I still 
receive From: <please.post@publicly.invalid> on a mailing list.  Rejecting that 
risks getting unsubscribed.  Perhaps mailing lists deserve a special permission...


Best
Ale
--