Re: [dmarc-ietf] ARC vs reject

Michael Thomas <> Sun, 06 December 2020 00:42 UTC

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To: Dave Crocker <>, John Levine <>,
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From: Michael Thomas <>
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Date: Sat, 5 Dec 2020 16:41:57 -0800
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Subject: Re: [dmarc-ietf] ARC vs reject
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On 12/5/20 4:21 PM, Dave Crocker wrote:
> On 12/5/2020 3:37 PM, Michael Thomas wrote:
>> "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.

How can me pointing out that you would call that an ad hominem, become 
ad hominem?

This is the bizzarro world that caused me to leave the last time.

> 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.

Oh yeah, I just missed the implied royal you in the reply directed at me 
from somebody who has a long history of antagonism to me including petty 
5xx messages from direct mail to him. Whatever was I thinking in the 
Panglossian world we live in?

>> 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.
You are fixated on what the receiver must or must not do. I never said 
anything about that. That is a strawman. I'm pointing out that ARC is 
trying to get two states out of reject where there only is one. It is 
certainly not unreasonable for my bank to say "please reject anything 
that is not by the letter of the law". I don't want somebody to figure 
out how to game all of this ARC stuff to phish me from my bank. That is 
far from unreasonable.

But you can say, no I am smarter than those banks and I REALLY REALLY 
mean it, but I don't care.