[TriLUG] Another seal broken... thinking of installing a C/R anti-spam system

[Magnus]

Cristobal Palmer wrote:
> You have a better suggestion?
> 
> Greylisting? Nolisting? CAPTCHA? Something else?

OpenBSD's spamd is one of the most brilliant ideas going.  The best 
adaptation spammers have made to deal with it is simply to recognize it 
and disconnect before the spam engine gets stuck.

I've had mixed results with greylisting.  The problem is that some ISP's 
and corporations have a pool of outbound smtp servers that will retry 
from different hosts, so you may not get the same tuple on the retry and 
the mail is delayed again and again and again until it is eventually 
timed out.

Anything that requires a sender to send a mail and then *do something 
else* (be it a CAPTCHA or a response or whatever) is going to be 
aggravating as hell and result in one of the most undesirable 
conditions: loss of legitimate mail.