Closing Ports

[parasailing]

Hi All,

I am planning to block access to Napster,Kazaa, and the various other ports that users use to download music. However, I know some of my users will probably circumvent this by tunnel traffic through open ports such as http. Is there some sort of software or hardware ie Pix, Cisco router, or some other device that allow for inspection of such packets and will taken immediate action to prevent such connections?

Any help would be greatly appreciated.