This is cool.
The approach involves building a virtual SOHO network, which is in turn connected to a virtual Internet. Both the virtual LAN and WAN are populated with virtual machines. The suspected worm is introduced into this environment, and executed therein. The whole system is closely monitored as execution progresses in the isolated environment, and data is amassed describing what the suspected worm did as it executed. This data is then processed by the system in an attempt to automatically determine whether or not the suspect programming is performing actions indicative of a worm or internet-aware malware.
You can find the complete paper here: “An Environment for Controlled Worm Replication and Analysis“


