Re: [dmarc-ietf] A policy weaker than quarantine, yet better than none

Alessandro Vesely <vesely@tana.it> Mon, 18 January 2021 18:48 UTC

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To: John R Levine <johnl@taugh.com>, dmarc-ietf <dmarc@ietf.org>
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From: Alessandro Vesely <vesely@tana.it>
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Subject: Re: [dmarc-ietf] A policy weaker than quarantine, yet better than none
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On Mon 18/Jan/2021 18:54:15 +0100 John R Levine wrote:
> On Mon, 18 Jan 2021, Alessandro Vesely wrote:
> 
>> At least, we could specify in the General Record Format that unrecognized 
>> policies should be treated as p=none.
> 
> Absolutely not.  Any DMARC record with an invalid p= is just broken.  We write 
> standards that say how to interoperate, not how to guess what other people had 
> in mind when they implemented it wrong.


Right, but IF one day we introduce a new policy, we'll have to be compatible 
with installed base.  Please don't reply that we'll NEVER introduce new policies...

BTW, the current spec does not mean that an invalid p= implies the DMARC record 
is broken.  If it did, it wouldn't say to check rua= in that case.


Best
Ale
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