Spam Filtering

We have implemented SPAM filtering technology on our CentOS servers. The “Mail Abuse Prevention System” or MAPS is a not for profit organization committed to defending the internet’s email system from spammers. We have implemented the MAPS Spamhaus “Zen” technology. ZEN is the combination of all Spamhaus DNSBLs into one single powerful and comprehensive blocklist to make querying faster and simpler. It contains the SBL, the XBL and the PBL blocklist.
A DNS-based Blackhole List, or DNSBL, is a means by which an Internet site may publish a list of IP addresses, in a format which can be easily queried by computer programs on the Internet. As the name suggests, the technology is built on top of the Internet DNS or Domain Name System. DNSBLs are chiefly used to publish lists of addresses linked to spamming.
For more info you may visit http://www.spamhaus.org/zen/
While this is a very good front line filter, it will not eliminate spam completely but should help reduce it at the server level. We therefore highly recommend local spam filtering. Windows Live Mail has a pretty good built in spam filter and is a good POP3 mail client. There are also many other third party spam filters that work very well with your local mail client software. SpamBully is spam filtering software that we have personally used and have had very good results with. However, there are many to choose from for just about every mail client.