But DMARC is email authentication best practice. Sure, some legacy email things are having some minor teething problems with it, but it's clearly the way to go. Because it introduces authentication. Now all the spammers will have to open their free yahoo accounts first, before sending email! That's a great step forwards! Security! Best practice! Lloyd Wood http://about.me/lloydwood ________________________________________ From: ietf [ietf-bounces@xxxxxxxx] On Behalf Of John R Levine [johnl@xxxxxxxxx] Sent: 14 April 2014 04:28 To: Dave Crocker; IETF general list Subject: Re: DMARC: perspectives from a listadmin of large open-source lists >> Yes, that's the 1980s percent hack. > intended recipient. While a bit inefficient -- and probably will emerge as > an attack vector (sigh) -- it's a plausible mechanism. Right -- something is seriously wrong with DMARC as used if we need to invent new phish syntaxes to work around it. R's, John