I'm at uni, and am connected to the internet through a high-speed sever called resnet. When first connecting your computer you are asked for a username and password. Having entered these, all programs work fine, internet explorer, games, steam, you name it.
However, if you try pinging a remote server or tracing the route to a remote server, it is immediately blocked by said resnet server. Also, there's thousands of students on this server, and the server stops you from seeing other computers on the network through command prompt.
Of course, being a student with too much time on my hands, I want to find a way around this through command prompt, find my housemate's computer on the network and mess with it 8D