Re: DMARC from the perspective of the listadmin of a bunch of SMALL community lists

Douglas Otis <> Thu, 17 April 2014 07:08 UTC

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Subject: Re: DMARC from the perspective of the listadmin of a bunch of SMALL community lists
From: Douglas Otis <>
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Date: Thu, 17 Apr 2014 00:08:08 -0700
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On Apr 16, 2014, at 11:00 PM, wrote:

>> On Sat, Apr 12, 2014 at 4:35 PM, <> wrote:
>>> The underlying technical issue is that the two technologies DMARC is built
>>> on -
>>> DKIM and SPF - both attach additional/restrictive semantics to
>>> longstanding mail
>>> system fields. (Broadly speaking, From: for DKIM and MAIL FROM for SPF.)
>> Something's amiss here.  What new semantics does DKIM attach to From:?  As
>> far as I know, it only requires that the field be signed.  It doesn't
>> require that it be interpreted in a particular way or that it contain any
>> particular value.
> I was trying to be brief. Yes, I'm well aware that DKIM can be used in other
> ways. This entire discussion is within the context of DMARC here. Do you
> disagree that DMARC's use of DKIM and SPF assign additional semantics to header
> and envelope from fields respectively?

Dear Ned,

Murray is correct. DKIM does not create special From header field semantics.  However, DMARC semantics are similar to those of ADSP while avoiding some shortcomings.
>>> Like it or not, the IETF published a draft that defines certain mechanisms
>>> which, if used improperly by a large provider, cause serious problems for a
>>> large number of people. The text describing the consequences of the use of
>>> those mechansisms in the drafts is, IMO, entirely inadequate.
>> It's the same document that was posted on other web sites for some time,
>> and was in use by a number of operators (including Yahoo) long before it
>> went into the datatracker.
> So?
>> As it's only a draft, there's ample opportunity to make such improvements.
> You're missing the point. When Yahoo made this change wouldn't it have been
> nice to be able to point to the draft and say, "This is explicitly contrary
> to what the draft says"?


>> Also: By "the IETF published a draft", are you talking about an RFC, or the
>> DMARC base draft?
> The draft, of course.
>> It seems extreme to lay blame on the IETF in general
>> merely for having an open mechanism by which to post a draft for all to see
>> and discuss.  A "Request For Comment", as it were. 
> You may think it extreme. I don't. I think the IETF's politics have led to  it
> inching closer to moral hazard territory for a long time, and with this
> incident it has stepped in it.

This disruption should be shared with the provider that has already enumerated 30,000 mailing-lists but made no effort to establish a means to verify these sources and to safely assert specific exceptions to DMARC alignment requirements. This ability is desperately needed before applying DMARC reject on user accounts.  I'll be happy to modify either ATP or ATPS to permit these exceptions without the need to alter mailing-list. 

>> Are you suggesting that
>> process should be closed or moderated somehow?
> What I suggested is that we need to have a serious discussion of what, if
> anything can be done to ameliorate the damage in this case. Others have
> suggested that we also need to look at how to prevent this from happening
> in the future. I concur.
>>> And it's not like we didn't know. As others have pointed out, this issue
>>> existed in the earlier ADSP proposal. It was given insufficient attention
>>> there as well.
>> As with any draft, its content is only as good as its contributions and the
>> reviews it got.
> I hope you're not saying that this is now fault of the people who failed to
> contribute to the draft.

These comments were made more than one year ago and ignored.

>>> Of course the IETF can fall back on the usual excuses, including, but not
>>> limited to:
>>>    Yahoo, of all ISPs, should have known better
>>>    We don't tell people what to do
>>>    It was just a draft
>>>    It was never intended to be a standard
>>>    We're not the Internet Protocol Police
>>>    etc.
>>> I'm sorry, but this time none of these dogs are hunting for me. An
>>> attractive
>>> nuisance is an attractive nuisance, and this is what the IETF has, albeit
>>> with
>>> the best of intentions, managed to create.
>> I would add to this that, by its ultimate inaction in the face of a
>> protracted period of abuse and attempts by participants to solve that
>> problem within its procedures, the IETF has abdicated any authority it may
>> have had.
> That may be your assessment. Given subsequent comments from other people,  mine
> is now that this effort was looking for a rubber stamp, didn't like it when
> that didn't happen, and proceeded to skirt around the edges of the process.
> With disasterous results.

Agreed. They seemed motivated into creating a system finely tuned for bulk senders while ignoring needs of individual users.  After all, bulk mailers contribute to their bottom line, but they may find users voting with their feet which may have the effect of reducing ad revenues due to fewer eyeballs.

Douglas Otis