[69300] in North American Network Operators' Group
Re: Anti-Spam Router -- opinions?
daemon@ATHENA.MIT.EDU (Dan Hollis)
Mon Apr 5 15:33:54 2004
Date: Mon, 5 Apr 2004 12:33:15 -0700 (PDT)
From: Dan Hollis <goemon@anime.net>
To: Paul Vixie <vixie@vix.com>
Cc: nanog@merit.edu
In-Reply-To: <g3d66m2qkf.fsf@sa.vix.com>
Errors-To: owner-nanog-outgoing@merit.edu
On 5 Apr 2004, Paul Vixie wrote:
> that's why greylisting has been so effective -- to combat it the
> spammers would have to add the one thing they cannot afford: "state."
> see http://www.rhyolite.com/dcc/ for how to get started.
why is 'state' so hard to afford? they already have a list of email
addresses to spam, and they already have compromised boxes -- those are
the big costs for spammers. another byte of state per email address is
cheap (or if you are clever, a single bit stored in the email address
itself, which doesnt cost you anything).
i see greylisting being effective only as long as it doesnt get widely
deployed. as soon as greylisting starts having any impact on spammers,
they'll start spooling -- and it is very cheap to do so. after all, just
about everything on compromised boxes costs them nothing. and compromised
are the source of 99.9999999% of all spam.
-Dan
