I've been running my Xbox live through the network at my school for the last couple of years. This year they required everyone to install a program called Impulse, which checks whatever is on the network for antivirus promgrams and spyware removal. Because of this I can only connect to Xbox Live for 3 or 4 minutes before I lose my connection. Any tips on a way to by pass Impulse?
http://techlore.com/forum/thread/14041/
My method there of connecting the XBox to your computer should do the trick.