Re: [dmarc-ietf] Revisiting the Race Condition in draft-crocker-dmarc-sender-01

[John Levine <[e-mail]>]

In article <[e-mail]> you write:
>[What to do when From and Sender DMARC have different results ?]
>
>When I first posed this, the answers I got were along the lines of
>"Receivers will do what they want, like they've always done", and that's
>certainly true if the behavior isn't mandated in the RFC (and maybe even if
>it is). That's cool and all, but doesn't "Receiver's Choice" risk
>continued, or perhaps even worse, breakage of the primary problem that this
>document is trying to fix?

You're right, the sender tweak only makes sense if the sender result
is preferred. Otherwise a sender result can only make it less likely
that a message is delivered, and that wouldn't be very useful.

As always, a successful result doesn't mean not spam, it just means it
didn't fail DMARC. I expect some non-normative advice would be
helpful, pointing out that this is useful for third party senders, and recipient
systems will have to come up with their own idea about which third parties are
credible.

It occurs to me it's likely to be the same list of third parties whose ARC seals
are credible.

R's,
John