Greylisting -- Was: Anti Spam

[John Levine]

>Cellular operators know that their clients expect speedy
>delivery of SMS, including those sent via SMTP.

Actually, in my experience SMTP to SMS gateways can have significant
delays unrelated to greylisting.  Travel agencies like Orbitz send out
notices about flight changes and delays via SMTP->SMS and as often as
not I only get the notice when I turn my phone back on after the
delayed flight has landed.

>Have you confirmed with your cellular operator that they don't offer
>additional gateways; e.g. based on ICQ, HTTP and whatnot?

There are third party services that do this.  For example,
clickatell.com offers a HTTP POST to SMS gateway quite cheaply, about
10 cents a message at low volumes.

Having been dealing with spam for over a decade, I cannot tell you how
tired I am of people whining that the world better not implement some
effective anti-abuse technique because it would cause them a minor
inconvenience due to their particular uncommon setup.  Spam sucks.
Deal with it.

R's,
John