Re: [dmarc-ietf] Comment on draft-ietf-dmarc-psd

Alessandro Vesely <> Wed, 04 December 2019 10:39 UTC

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Subject: Re: [dmarc-ietf] Comment on draft-ietf-dmarc-psd
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On Wed 04/Dec/2019 08:42:09 +0100 Murray S. Kucherawy wrote:
> On Mon, Nov 11, 2019 at 2:21 PM Dave Crocker <
> <>> wrote:
>>> * add text to the PSD draft making it clear that what it's describing is
>>>   an experiment whose outcome will be taken only as feedback to the
>>>   revision of the standard (i.e., this is not intended to be the final form
>>>   of anything), and it is not intended to be deployed outside of the
>>>   experiment's participants;
>>  Forgive me, but while everyone involved in this has extensive experience
>>  and is trying to solve a real and serious issue, this is an astonishingly
>>  naive view.
> I don't think it's based entirely on naivety.  I think there's a healthy dose
> of feeling that the experiment as it's currently designed couldn't possibly
> scale to "the entire domain namespace" and/or "all servers on the Internet", so
> in that sense from where I sit there's a built in safeguard against this
> becoming a permanent wart.

After installing the DKIM/DMARC filter that implements PSD, I can say that the
impact is unnoticeable.  I didn't carry out precise measurements, I just didn't
notice any delay.  Perhaps because I don't get so much mail from, but I
don't think I could reliably measure a positive delay even if I were a strict
correspondent of Boris.

> Rather, it's primed as a possibly useful data collection exercise.

Kurt also talked about reporting some findings.  I'm embarrassed, I have no
idea what I, as a receiver, should report.  What data should I, and other
receivers collect?

IMHO, the experiment should be conceived as having it run by as many receivers
as possible, so as to have a noticeable effect on senders.  They can collect
aggregate reports and make a comparison.