Re: [dmarc-ietf] Nitpicky questions about DMARC record syntax

"John R Levine" <johnl@taugh.com> Wed, 16 January 2019 17:26 UTC

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Date: 16 Jan 2019 12:26:10 -0500
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From: "John R Levine" <johnl@taugh.com>
To: "Kurt Andersen" <kurta@drkurt.com>
Cc: dmarc@ietf.org
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Subject: Re: [dmarc-ietf] Nitpicky questions about DMARC record syntax
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> Is there really a benefit in filtering out people/organizations that are
> not fastidious in the use of whitespace and character case?

Maybe, but that's not what standards are about.  The point of a standard 
is to say here's what you do if you want to interoperate.  I have never 
found it productive to speculate about what you might or might not want to 
do when you run into people who didn't read the spec.

In the particlar case I ran into, they're all in .bank and I would expect 
that .bank's auditors would contact their clients and get them to fix 
things.  They have worse problems than wrong capitalizations, like banks 
publishing two different DMARC policies, or one that includes "pct:1" 
whatever that's supposed to mean.

Also, in this case keep in mind that the default is not to filter, so 
you're not going to lose any mail.  You might receive a few more phishes.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly