Re: [spfbis] Question about SPF checks based on RFC 7208

"Stuart D. Gathman" <stuart@gathman.org> Mon, 02 May 2016 02:43 UTC

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Date: Sun, 1 May 2016 22:43:33 -0400 (EDT)
From: "Stuart D. Gathman" <stuart@gathman.org>
To: Scott Kitterman <spf2@kitterman.com>
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Subject: Re: [spfbis] Question about SPF checks based on RFC 7208
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Implementations will *always* lookup only one of A/AAAA - the type
matching the connect IP.  So taking your second option would mean that
A,MX mechanisms would never be void!

On Sun, 1 May 2016, Scott Kitterman wrote:

> I think it might make sense that to clarify that an mx mechanism is only void
> if neither A nor AAAA exist.  Implementations could either do the extra lookup
> or just not count it as void if only looking up one.  From an interoperability
> perspective, I think either would be fine.

-- 
 	      Stuart D. Gathman <stuart@gathman.org>;
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.