Anti-Spam Router -- opinions?

Mon Apr 5 19:33:15 UTC 2004

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