Best way to block P2P programs like BearShare?

[Queasy]

Long story made short - brother-in-law is killing my internet connection running his damn bearshare all day. I want to block it cause he's being a typical stupid teenager and downloading stuff he shouldn't be.

Suggestions?

I've got a Linksys WRT54G router flashed with DD-WRT. Supposedly, the next DD-WRT update is supposed to be easy to block certain applications.

Best suggestions I've found so far through google is to port forward him to a non-existant IP or to throttle his connection.

 

[Nothinman]

If Bearshare uses an easily determined set of ports, yes you can stop it quite easily. But if it's dynamically changable, then it'll be much more difficult unless you don't think he'll be able to figure out how to change them.