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

Alessandro Vesely <vesely@tana.it> Thu, 17 June 2021 11:13 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: Thu, 17 Jun 2021 13:12:44 +0200
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Subject: Re: [dmarc-ietf] Ticket #11 (and #112) - Proposed language
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On Wed 16/Jun/2021 20:02:21 +0200 John Levine wrote:
> Let's close ticket #112 and stop.


I agree that the definition given in the PSD is clear enough:

    For DMARC purposes, a non-existent domain is a domain for which there
    is an NXDOMAIN or NODATA response for A, AAAA, and MX records.  This
    is a broader definition than that in [RFC8020].

However, by that definition a domain with a Null MX [RFC7505] is an existent 
domain for DMARC purposes.  Perhaps this apparent contradiction could be noted 
by adding a sentence somewhere, for example:

    Even though the bare existence of a domain does not entail that it can send
    or receive email, the presence or absence of the relevant DNS RRs determines
    which policy between sp= and np= is applicable.  If a DMARC record is found
    for a domain that would be non-existent by the above definition, the p=
    policy defined there is still the one to be applied.

Would that add clarity?


Best
Ale
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