Re: [dmarc-ietf] PSD simplification

Dave Crocker <> Wed, 12 December 2018 18:00 UTC

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To: John R Levine <>
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From: Dave Crocker <>
Organization: Brandenburg InternetWorking
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Date: Wed, 12 Dec 2018 09:59:59 -0800
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Subject: Re: [dmarc-ietf] PSD simplification
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On 12/12/2018 9:47 AM, John R Levine wrote:
> On Wed, 12 Dec 2018, Dave Crocker wrote:
>> 3. Given queries for MX record, don't we already have massive exposure 
>> of this privacy-related info in DNS activity?  How would this be so 
>> much more (and/or worse)?
> Particularly with large passive DNS databases, you're right.  I believe 
> that Scott's point was that we can try not to make it worse.

This is a point worth pressing on.  Hard.

The source of the pressure is that the cost of a queriable registry is 
high.  Very, very high.  So creating one needs to have a very compelling 
justification.  I don't see how this one comes close.

>>>  a lot of mail.  (Real mail, they're the county govermnent.)  This is
>>>  easily addressed by clients ignoring the report advice in the OD
>>>  parent record.
>> What does it mean for a /client/ to ignore the advice in the OD parent 
>> record?  I thought that record was for servers.
> I meant the DNS client, which is likely to be the mail server receiving 
> a message.

Besides retrieving information and passing it up to its caller, the DNS 
client has nothing at all to do with using advice in an OD parent 
record.  Hence my confusion about your text.  So I think you meant "This 
is easily addressed by receivers ignoring the report adivce in the OD 
parent record."

Contrary to many other occasions, I'm not being this picky just for fun. 
  These topics seem to engender confusion in lots of folk and lots of 
discussions, and so I think it important to be very careful about 
terminology and references.


Dave Crocker
Brandenburg InternetWorking