One of my favorite weekly tech mags, Processor, did an interesting article on a relevant topic -Skype the popular P2P Internet Telephony program. As a general rule, P2P (peer-to-peer) apps, while they may offer valuable functionality, can be a thorn in the side of System Administrators as they don't offer the client/server centralized control often necessary to manage software. In many cases P2P apps serve no business purpose and simply distract workers in the same way I get distracted by Fantasy Football -just during my lunch break of course :). In the Processor article, the author Kurt Marko, does a good job of covering tools available to detect and control Skype. The two technologies he presents are Content Filtering (monitoring the type of traffic on the network) and Network Access Control (quarantining a system that does not follow pre-establish policy). These are excellent technologies to 1a. Prevent Skype from working across a firewall and out onto the Net, 1b. Detect the network traffic, and 2. Prevent a machine with Skype installed from entering the network. In my opinion, it really takes BOTH technologies to mitigate the threat. Another third technology fits into that mix as well.