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

John Levine <johnl@taugh.com> Fri, 07 May 2021 21:13 UTC

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From: "John Levine" <johnl@taugh.com>
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Subject: Re: [dmarc-ietf] Ticket #111 - MX/A/AAAA test needs justification
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It appears that Douglas Foster  <dougfoster.emailstandards@gmail.com> said:
>Is there a query or collection of queries that can ensure that we only
>accept results from the identifier domain and not from the parent?

This is a meaningless question.  DNS queries ask about a specific name
and RRTYPE and you get back the answer for that name and RRTYPE.

>*Wildcard DNS:*
>
>Wildcard entries create intentional ambiguity.

That is simply false.  Wildcards are perfectly well defined.  I have
occasionally found wildcard MX records to be useful.

I have taken another look at ticket #111 and found that the questions
it asks misunderstand both the way that the DNS works and the way that
SMTP has used the DNS since RFC 1123 over 30 years ago.

Please close this ticket, there is nothing to fix.

R's,
John