Re: [Ietf-dkim] Adding an aim= tag to DKIM Signature Tag Specifications

Alessandro Vesely <> Wed, 13 May 2020 07:36 UTC

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To: "Murray S. Kucherawy" <>
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From: Alessandro Vesely <>
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Date: Wed, 13 May 2020 09:36:44 +0200
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Subject: Re: [Ietf-dkim] Adding an aim= tag to DKIM Signature Tag Specifications
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On Wed 13/May/2020 08:03:27 +0200 Murray S. Kucherawy wrote:
> On Tue, May 12, 2020 at 11:14 AM Alessandro Vesely <> wrote:
>> On Tue 12/May/2020 19:09:55 +0200 Murray S. Kucherawy wrote:
>>> On Tue, May 12, 2020 at 9:30 AM Alessandro Vesely <> wrote:
>>>> On Tue 12/May/2020 17:48:38 +0200 Murray S. Kucherawy wrote:
>>>>> On Tue, May 12, 2020 at 1:20 AM Alessandro Vesely <> wrote:
>>>>>> On Mon 11/May/2020 20:23:12 +0200 Murray S. Kucherawy wrote:
>>>>>>> Indeed; why would I believe what any given domain claims in this tag?
>>>>>> If you trust the domain, you can as well trust their tagging.
>>>>> If you trust the domain, you don't need their tagging.
>>>> Why not?  I may trust gmail, say.  Yet, in order to learn what 
>>>> restrictions they apply to the From: I have to create an account and
>>>> try. There is no standard location where they declare their policy in
>>>> a machine-readable manner, and policies written in legalese are even
>>>> less readable...>>>
>>> What would you do with that information if you had it?
>> I think I'd copy it to comments in the corresponding A-R header field. 
>> That would make A-R stanzas more eloquent.>>
> So this is ultimately for human consumption?  Now I'm really confused.

It is a semantic addition about a question that people keeps asking.  Maybe its
usage becomes apparent once we get used to it, or maybe not.  It is the fact
that that question is frequently asked which triggered this thread and makes it

>>> [...]
> If you believe that header fields written by are true to life,
> what more can these tags tell you?
>> Hey, what if gmail used different selectors for newcomers?
> What would you do with that information?  Or given your answer above, what
> would one of your users do with that information?

A-R details can be used to set IMAP keywords, to sort messages in different
folders, with varying colors or icons.  These techniques are quite helpful,
especially with busy mailboxes.

The destiny email messages is not a Boolean read-or-kill.