Extreme Spam Reduction: "The guns... they've stopped"

On September 9 2007, Jeff Ballard and David Parter gave a presentation to LOSPA-Madison about their experiences using mailfromd and variable greylisting to reduce spam:

The guns... they've stopped: Extreme Spam Reduction

Jeff Ballard, University of Wisconsin Computer Aided Engineering
David Parter, University of Wisconsin Computer Sciences Department

"The guns... they've stopped." That is what one of our users said after we improved our anti-spam configuration.

The UW College of Engineering and Computer Sciences Departments have drastically reduced the amount of spam. This not only pleases users, but has significantly reduced the load on mail servers, mail gateways, and spam assassin servers. We have done this through a method of demerits and aggressive greylisting, implemented using the mailfromd package.

We will describe our configuration, lessons learned, and some "gotchas". We expect everyone else to chime in for questions, answers, and discussion.

Here are the slides from the talk (pdf) and a the mailfromd configuration file from the UW CS department.