Re: [dmarc-ietf] ARC questions

John R Levine <johnl@taugh.com> Wed, 02 December 2020 22:53 UTC

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Date: 2 Dec 2020 17:53:33 -0500
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From: "John R Levine" <johnl@taugh.com>
To: "Michael Thomas" <mike@mtcc.com>, "Brandon Long" <blong@google.com>
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Subject: Re: [dmarc-ietf] ARC questions
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> Which could trivially be added as an extension to DKIM and Auth-Res negating 
> the need for the Seal altogether since DKIM can directly sign the old 
> (renamed) auth-res. I can understand for an experiment not wanting to touch 
> dkim or auth-res, but for something standards track less is more.

I still don't get it.  I suppose the ARC group could have done something 
to register extra tags for DKIM-Signature and A-R and tried to do 
something about the fact that if a message passes through the same network 
twice, the first A-R will be deleted, and try and find and turn off all of 
the places where mailing lists helpfully delete DKIM signatures that no 
longer are valid, and what they came up with wouldn't work a whole lot 
worse than ARC does.

But why bother?  The IANA header field registry currently has 419 entries. 
Why is it a crisis if it increases to 422 rather than 420?

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