public blacklists

[Paul Howarth]

Ow Mun Heng wrote:
> On Thu, 2004-12-09 at 02:54, Scot L. Harris wrote:
>>The SURBL option examines the URLs in the spam messages and checks
>>various block lists.  If they show up on the block list the score is
>>increased appropriately.  
> 
> I was just asking that question. Thanks for clearing that up. So,
> effectively, it's just another form of greylisting then.

No, greylisting is a completely different thing. Greylisting ensures that the 
sending server is a proper MTA that retries when it sees a temporary failure 
during a delivery attempt. Most spamware does not do this, hence greylisting 
stops lots of spam. SURBL is looking at the message body after delivery and 
scoring it as likely to be spam or not based on the URLs found there. Two 
completely different things.

Paul.