| Blacklist: Pros: It directs known, active Spam floods into a tarpit. This slows down the criminals. Cons: Zombie computers that send using an ISP's mail server will cause false positives. Greylisting: Pros: Incredibly effective; currently blocking nearly all inbound Virus and Trojan traffic. Cons: The first E-mail we see from a given Mail Server to a given customer will be delayed hours. Spamhaus: Pros: Well-maintained and not overly-aggressive service used by many ISPs. Cons: Some inevitable inertia both adding and removing listings. Backscatter: Pros: Deletes Non-Delivery Reports. Cons: Domains with List servers need to get Non-Delivery Reports. Clam Antivirus: Pros: Very effective. Cons: Few if any. Spamassassin: Pros: Will identify UCE otherwise missed. Cons: CPU intensive and the database can be corrupted by Spammer tricks. Perlscan: Pros: Stops most macro viruses and other Microsoft-specific malware. Cons: Fussy about attachments. |