Re: [dmarc-ietf] A policy for direct mail flows only, was ARC questions

John Levine <johnl@taugh.com> Sat, 05 December 2020 18:29 UTC

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From: "John Levine" <johnl@taugh.com>
To: dmarc@ietf.org
Cc: blong@google.com
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Subject: Re: [dmarc-ietf] A policy for direct mail flows only, was ARC questions
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In article <CABa8R6spYyZDhzEnQ=txdoLOO1Ek1MAryW6ioAsur1_mEvdXkA@mail.gmail.com> you write:
>mailing list to mailing list mail is very common in GSuite, but maybe we're
>a special case. 

I dunno how special that case is, but there are lots of cases where mail passes
through multiple layers of ARC signing mutations.

I routinely get mail from Microsoft's farm with an ARC seal or two
that has never been near a mailing list. Any time a MS user sends a
message to one of my lists, it'll emerge with at least two ARC
signatures.

R's,
John