I got same problem where my friend hogging the bandwidth using p2p software and at the same time he open bittorrent client. I found it quite unfair to me since im the one who pay for the line and even i ask him to pay halves of the rent, im still at disadvantages.

I'm using D-link DSL-2540T adsl router, is there any way or step by step how to limit the bandwidth to my friend's pc?

Thx