Re: [dmarc-ietf] Consensus Sought - Ticket #47 (Removal of "pct" tag) - With Interim Notes

Todd Herr <> Thu, 17 June 2021 13:38 UTC

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From: Todd Herr <>
Date: Thu, 17 Jun 2021 09:38:02 -0400
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Subject: Re: [dmarc-ietf] Consensus Sought - Ticket #47 (Removal of "pct" tag) - With Interim Notes
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I have closed the subject ticket and incorporated relevant text
changes in draft-ietf-dmarc-dmarcbis-02,
which will be published on Datatracker as soon as the chairs have a chance
to do so.

The relevant text changes here include clarification of the meaning of the
pct tag as well as a much longer discussion of message sampling and the
limitations inherent in the application of the pct tag.

The text changes all fall under the umbrella of "proposed text", and I
expect there will be further discussion of the topic.

On Fri, Jun 4, 2021 at 4:00 PM Tim Wicinski <> wrote:

> +1 With Mr Levine's line of thinking.
> I also agree with keeping pct= tag.
> tim
> On Thu, Jun 3, 2021 at 7:16 PM Dotzero <> wrote:
>> On Thu, Jun 3, 2021 at 6:17 PM John Levine <> wrote:
>>> It appears that Alessandro Vesely  <> said:
>>> >On Thu 03/Jun/2021 05:45:33 +0200 Murray S. Kucherawy wrote:
>>> >> I don't understand what "demeaning a domain's policy" means.
>>> >
>>> >I meant to say that p=quarantine; pct=0 is to be considered a strict
>>> policy to
>>> >all effects.  Saying so should prevent reasoning something like "Oh,
>>> they said
>>> >quarantine, but since pct=0 it is somewhat faked, so I'll skip X",
>>> where X
>>> >could be rewriting From:, displaying a BIMI image, record aggregate
>>> data, or
>>> >any other action that might depend on the policy.  That is to say pct=0
>>> does
>>> >not alter the value of p=, otherwise testing becomes a nightmare.
>>> If we agree that's what we mean, that's what we should say, e.g., add
>>> something
>>> like this:
>>>  Senders may use pct=0 to signal an intention to apply a stricter
>>>  DMARC policy in the future, and to request receivers that do special
>>>  processing based on DMARC policy to do that processing. Examples of
>>>  special processing might include mailing list software rewriting
>>>  addresses in From headers.
>> As long as we get the wording right, I agree with your line of thinking
>> John. Again, we don't have insight as to the extent that receivers will
>> honor the request.
>> Michael Hammer
>> _______________________________________________
>> dmarc mailing list
> _______________________________________________
> dmarc mailing list


*Todd Herr* | Technical Director, Standards and Ecosystem
*m:* 703.220.4153

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