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Re: [dmarc-ietf] DMARCbis WGLC Issue 132 - 5.5.1 and 5.5.2 SHOULD vs MUST (was Another point for SPF advice)

Alessandro Vesely <vesely@tana.it> Fri, 15 March 2024 08:48 UTC

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Original-Subject: Re: [dmarc-ietf] DMARCbis WGLC Issue 132 - 5.5.1 and 5.5.2 SHOULD vs MUST (was Another point for SPF advice)
Author: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] DMARCbis WGLC Issue 132 - 5.5.1 and 5.5.2 SHOULD vs MUST (was Another point for SPF advice)
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On Thu 14/Mar/2024 20:23:01 +0100 John Levine wrote:
> It appears that Scott Kitterman  <sklist@kitterman.com> said:
>>> SPF it treated in multiple places.  We cannot warn against a bad practice in
>>> one place (135) and recommend it unconditionally in another (132).
>>
>>That is exactly how one handles Security Considerations.  So 132 says do SPF.  
>>Security Considerations gives you stuff to think about how you do SPF.  There's 
>>not need to embed mitigations for the considerations throughout the draft 
>>(someone with more IETF experience than me, please correct me if I'm wrong 
>>about this).
> 
> If you're going to provide implementation advice for SPF, which I still think is
> a bad idea, security considerations is indeed the least bad place to do it.


I agree.

The point here is not to give a questionable MUST.  Telling people they MUST 
grant a pass to /every/ source is questionable, isn't it?


Best
Ale
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