Re: [dmarc-ietf] Sender vs From Addresses

Dave Crocker <> Wed, 24 March 2021 17:26 UTC

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To: Ken O'Driscoll <>, Charles Gregory <>
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From: Dave Crocker <>
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Date: Wed, 24 Mar 2021 10:26:46 -0700
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Subject: Re: [dmarc-ietf] Sender vs From Addresses
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On 3/24/2021 4:54 AM, Ken O'Driscoll wrote:
> There is actually an existing working group draft discussing extending 
> DMARC to incorporate the 5322.Sender header, see 
> <>. That 
> document goes into considerable detail on how 5322.Sender could be 
> incorporated in the future.

To be possibly overly frank, I think the draft is stalled.  Given 
existing practice, there are challenges to fielding this, for 
incremental adoption, in a way that is reasonable and useful. (The 
Internet does not support 'flag' days.)

I am still, sometimes, mulling over the choices for this, but so far 
haven't come up with (or seen) ways to resolve the challenge.

An option the working group declined to pursue is to define an Author: 
field and leave the From: field to the 'handling' role DMARC has 
relegated it to.  The draft for this is being pursued outside of the 
working group.


Dave Crocker

Volunteer, Silicon Valley Chapter
Information & PLanning Coordinator
American Red Cross