Re: [dmarc-ietf] ARC questions

John R Levine <johnl@taugh.com> Mon, 23 November 2020 22:42 UTC

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Date: 23 Nov 2020 17:42:23 -0500
Message-ID: <ec7eb8b4-71a5-166-6d4b-49829e1bbcb2@taugh.com>
From: "John R Levine" <johnl@taugh.com>
To: "Dave Crocker" <dcrocker@gmail.com>, dmarc@ietf.org
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Subject: Re: [dmarc-ietf] ARC questions
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>> You know that a message came from a mailing list because you have your
>> list of IPs or DKIM signatures of lists you trust.
>
> Except that was not stated or, really, even implied in the text of the 
> message I was replying to.  Rather, something like that seemed to be taken as 
> an assumption, but without any clear foundation.

Well, OK, but it's still true.

>> ARC deals with the problem that most list software forwards everything
>> with a subscriber's address on the From: line and does a lousy job of
>> spam filtering.
>
> Forgive me but I believe misbehavior by mailing lists has never been 
> meaningfully documented for this work.  Quite the contrary.

I believe that Brandon has specifically said that Gmail sees this problem 
and that is why whitelisting mail from mailing lists isn't adequate.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly