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Re: [dmarc-ietf] Discussion: Removal of validation for external destinations (Ticket #76)

John Levine <johnl@taugh.com> Sat, 05 December 2020 18:33 UTC

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From: John Levine <johnl@taugh.com>
To: dmarc@ietf.org
Cc: Alex_Brotman@comcast.com
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Subject: Re: [dmarc-ietf] Discussion: Removal of validation for external destinations (Ticket #76)
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In article <MN2PR11MB4351D62302C7357DE653F8B4F7F00@MN2PR11MB4351.namprd11.prod.outlook.com> you write:
>Hello,
>
>There's currently a ticket that suggests that the requirement for external validation be removed.  Today, if
>example.com has an RUA that points at example.net, the latter must create a record as such:
>
>example.com._report._dmarc.example.net TXT "v=DMARC1"

Whether or not the mailbombing problem is a practical problem,
everyone has already implemented this check so I do not see what
problem we would solve by getting rid of it. It's not like the
test is expensive or publishing the record is hard.

I think it may somewhat mitigate hammering on third parties when
someone misspells its rua= target.

R's,
John

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