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

Alessandro Vesely <> Tue, 12 May 2020 08:20 UTC

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From: Alessandro Vesely <>
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Date: Tue, 12 May 2020 10:20:28 +0200
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Subject: Re: [Ietf-dkim] Adding an aim= tag to DKIM Signature Tag Specifications
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On Tue 12/May/2020 00:08:15 +0200 Dave Crocker wrote:
> On 5/11/2020 1:33 PM, Jim Fenton wrote:
>> There might also be the situation where a domain wants to delegate a key
> Hence my suggestion that figuring out such details is where discussion could
> get interesting, if only because people will raise all sorts of combinatorial
> theories, independent of demonstrated need, and this is a space with lots of
> combinatorials...

Besides delegated keys, some other obvious classes I'd propose —without
venturing to forge English keywords— are as follows:

* 1st class personal messages (with or without From: restrictions),

* mailing lists (with or without From: rewrite),

* bulk messages (including transactional confirmations, complaints, ...),

* forwarded mail (after severe/loose antispam filtering).

Perhaps, the keywords should be dash-separated jumbles of terms chosen from a
predefined grab bag, to allow for combinations.

On Mon 11/May/2020 21:52:28 +0200 Damon wrote:
> ... or is this only to add a layer of (potentially ignored) definitions?

Adding the definitions can be useful, given that so many people wonder about
what would a DKIM signature certify.

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.

On Mon 11/May/2020 19:30:10 +0200 Dave Crocker wrote:
> Oh, and then figuring out why and how they are useful to provide...

Left as an exercise to the reader?