Re: [dmarc-ietf] Ticket #111 - MX/A/AAAA test needs justification

Douglas Foster <dougfoster.emailstandards@gmail.com> Fri, 07 May 2021 00:02 UTC

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From: Douglas Foster <dougfoster.emailstandards@gmail.com>
Date: Thu, 6 May 2021 20:02:25 -0400
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To: IETF DMARC WG <dmarc@ietf.org>
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Subject: Re: [dmarc-ietf] Ticket #111 - MX/A/AAAA test needs justification
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I have begun data collection on the effectiveness of the MX and A tests.
 Wildcard DNS entries increase the frequency of false positives and reduce
the usability of the test.   For example, "msaqq189.ford.com" returns a set
of MX results, but I rather doubt that I made a lucky guess and found a
mail domain that Ford Motor actually uses.



On Thu, May 6, 2021 at 6:32 PM Jeremy Harris <jgh@wizmail.org> wrote:

> On 05/05/2021 12:28, Douglas Foster wrote:
> > Non-delivery reports are officially discouraged
>
> RFC 5321 Section 6.2 says the reverse.
>
> --
> Cheers,
>    Jeremy
>
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