Re: [dmarc-ietf] ARC vs reject

Dave Crocker <> Sun, 06 December 2020 00:21 UTC

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To: Michael Thomas <>, John Levine <>,
References: <20201205231059.2BA23290EDCD@ary.qy> <> <> <>
From: Dave Crocker <>
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Date: Sat, 5 Dec 2020 16:21:23 -0800
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Subject: Re: [dmarc-ietf] ARC vs reject
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On 12/5/2020 3:37 PM, Michael Thomas wrote:
> On 12/5/20 3:24 PM, Dave Crocker wrote:
>> On 12/5/2020 3:15 PM, Michael Thomas wrote:
>>> Can you keep your contempt for me off this list? This is not even 
>>> responsive to what I wrote, and is nothing more than an ad hominem.
>> Wow. It wasn't an ad hominem.
> "You can say, no I am smarter than those guys and I REALLY REALLY mean 
> it, but see 2) above."
> This is really not about questioning my intelligence. eye roll. If I 
> said the same thing to you, you'd be screaming bloody murder to the 
> chairs to try to get me banned again.

Note that what you have just done is, in fact, an ad hominem and 
arguably does violate IETF participation rules.

Again, the response you are objecting two exactly followed the 
linguistic form of the setup you offered.  As such, the response was not 
directly at you, the author of the posting, but at the hypothetical 
person you formulated.

> If the publisher of the DMARC record cannot accurately state its 
> desires/policy, that is a deficiency in the protocol. Reject means I 
> want you to reject it. It doesn't carve out exceptions. ARC is trying 
> to carve out exceptions. If it wants an exception, the originating 
> domain should have a say in whether it desires the receiving domain to 
> carve out an exception one way or the other.

The domain owner might want all sorts of unreasonable things. Having a 
way to let the domain owner publish demands that are widely ignored 
indicates a seriously flawed semantic model. And that is, indeed, the 
current reality for DMARC.


Dave Crocker

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