vgill@vijaygill.com (vijay gill) writes:
... That means that if I do get a mail purporting to be from citi from randomgibberish, I can junk it without hesitation.
agreed, that is what it means. however, and this is the important part so everybody please pay attention, if you can junk something "without hesitation," then spammers will stop sending that kind of "something." they make their money on clickthroughs, final sales, and referrals, which translates to one thing and one thing only: "volume." if the way to keep their volume up means "put SPF metadata in for the domains they use" or even just "stop forging mail from domains that have SPF metadata" then that is exactly what they will do. guaranteed. there's a bet here. you could bet that by closing off this avenue, SPF will force spammers to use other methods that are more easily detected/filtered, and that if you play this cat&mouse game long enough, it will drive the cost of spam so high (or drive the volume benefit so low) that it'll just die out. i lost that bet during my MAPS years. your mileage may vary, but to me, SPF is just a way to rearrange the deck chairs on the Titanic. we won't have decent interpersonal batch digital communications again before whitelists; everything we do in the mean time is just a way to prove that to the public so they'll be willing to live with the high cost of fully distributing trust. -- Paul Vixie