[dmarc-discuss] Display Names (was Re: Multiple From: addresses (was Re: Several remarks)_

[David F. Skoll]

On Tue, 31 Jan 2012 16:14:47 -0500
Andrew Sullivan <asullivan+dmarc at dyn.com> wrote:

> How can you as an upstream-DMARC checker know that something
> downstream isn't DMARK-oblivious and going to check the DKIM signature
> again?

In general, you don't.  In many cases, you can know it well enough (for
example, if you're running DMARC-checking on a corporate MX record and
don't let internal users forward mail off-site.)  But yes, it's a risk.

Regards,

David.