So ... What on earth is a Botnet?

"A botnet is comparable to compulsory military service for windows boxes" - Stromberg (http://project.honeynet.org/papers/bots/)

A Botnet is a network of computers that have been infected and are under the control of a hacker or group of hackers. Once they have computers under their control the hackers can use them to propagate viruses, send spam, launch attacks against web sites (distributed denial of service attacks or DDos) or any number of other suspect activities. Criminal gangs have even been known to “rent” their Botnets to other criminals. This is what occured during the recent Botnet experiment by the BBC http://itnetworksecurity.blogspot.com/2009/03/botnets-very-real-threat.html (not that I am comparing the BBC to criminals, you understand).

Botnets can consist of many thousands of compromised computers, with this number of machines under their control the people behind the Botnets can cause all sorts of chaos including Distributed Denial of Service (DDos) attacks against corporate web sites. Botnets are being used by criminal gangs to extort money – sending messages to companies threatening to take their website down unless payment is forthcoming.

One technique that is used in the fight against Botnets is called a honeypot. The idea of a honeypot is to provide an unprotected machine or set of machines and examine how attackers infiltrate the systems. A great site to read up on this topic more is The Honeynet Project (http://project.honeynet.org) which describes its own site's objective as "To learn the tools, tactics and motives involved in computer and network attacks, and share the lessons learned."