I need help with this. We have Verizon dsl internet.

Its being split 3 ways, and my brother is downloading porn and other pointless movies to slow the internet up for everyone else, and He always has a pass or something on his comp so i cant get in on his comp and mess with it.

HE connects to our internet with a ethernet cord into the back of the hub that connects to the router.

Is there anyway to block a port or is there anyway to stop his computer from connecting to frostwire without actually going on his computer?