BRAVE GNU WORLD

The computer industry has not found an easy solution to the problem of spam. Solutions vary, but combination of various approaches seems to make the most sense. One of the most useful approaches is to allow the mail server to filter messages before forwarding them to the user. Many projects are working on this problem, and we have looked at some of them in this column, SpamAssassin [5] for example. But this month we’ll focus on a different approach: filter networks. Many administrators have started applying multiple filters, combining spam and antivirus scanners, for example, or using multiple filters to achieve more hits. There are no limits to the effort you can put into this, but the more complex a system becomes, the more susceptible it is to configuration errors.