Re: [dmarc-ietf] Review of draft-kucherawy-dmarc-base-00 (was:Fwd: Eliot's review of the DMARC spec)

Franck Martin <> Sat, 06 July 2013 08:14 UTC

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From: Franck Martin <>
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Thread-Topic: [dmarc-ietf] Review of draft-kucherawy-dmarc-base-00 (was:Fwd: Eliot's review of the DMARC spec)
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Date: Sat, 06 Jul 2013 08:14:08 +0000
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Cc: "<>" <>, "Murray S. Kucherawy" <>, Eliot Lear <>
Subject: Re: [dmarc-ietf] Review of draft-kucherawy-dmarc-base-00 (was:Fwd: Eliot's review of the DMARC spec)
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On Jul 5, 2013, at 11:05 AM, SM <> wrote:

> Hi Murray,
> At 01:34 05-07-2013, Murray S. Kucherawy wrote:
>> In Section 15.8:
>>  "Many systems are able to scan the SMTP reply text to determine the
>>   nature of the rejection, thus providing a machine-detectable reason
>>   for rejection allows automated sorting of rejection causes so they
>>   can be properly addressed."
>> I don't think that it is a good idea to discuss about that as part of a protocol specification.
>> Why?
> The draft getting into heuristics.  This takes you away from protocol specification to things people do because "it works for them".  The straight answer is that I don't really know as it is a matter of whether the heuristics not working is really an edge case or something to seriously consider.
There is not much standardization of response codes from MTAs. There are extended response codes, but then you cannot deduct from them, if the problem is due to DMARC or other security policies. If I'm not mistaken, take the case of Facebook, refusing an email because you are not a friend of the recipient... Or the same error code could indicate SPF or DKIM or other protocol failure... Having the word DMARC in the text of the error message gives a lot of information for debugging a specific email. Consider also the error could be generated after a forwarder is trying to send an email... Without a proper hint of what is the reason of the reject it is very hard to know what really happened for a specific email.