Re: (DMARC) Why mailing lists are only sort of special

"Murray S. Kucherawy" <> Wed, 16 April 2014 18:41 UTC

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Date: Wed, 16 Apr 2014 11:41:20 -0700
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Subject: Re: (DMARC) Why mailing lists are only sort of special
From: "Murray S. Kucherawy" <>
To: John R Levine <>
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On Tue, Apr 15, 2014 at 7:18 PM, John R Levine <> wrote:

> The reason it's not special is that it's just the most visible example of
> a wide variety of legitimate useful mail that DMARC can't describe, and
> that are broken by DMARC policies other than p=none.

As I see it, this is probably the core of the stalemate.  I agree that
DMARC, and its various antecedents that we all know and love, can't
precisely describe mailing list traffic as it's currently defined.  What I
observe, though, is that there's typically lots of talk about what we can't
do to add that capability, and almost none about what's actually possible.
People get discouraged and give up.  This isn't a path to success.

I'm all for being as incremental and non-destructive as possible when
building these things.  I also don't think it's possible to be completely
invisible 100% of the time.

Sure, whitelisting is one possible solution.  Publishing a whitelist is
easy, but populating it, managing it, making it robust, making it fair, and
protecting it against fraudulent entries needs to be sorted out, whether
it's a public whitelist or a private one.  Are we certain, though, that
it's flatly impossible to adjust lists in such a way that their traffic
could be described by these mechanisms?