I know that pfsense is a very effective tool for restricting bit torrent traffic. I was wondering how it actually manages to do that ? There's not much information available on this. The more technical, the better.
As far as I know pfsense performs very simplistic traffic shaping where by it prioritizes traffic based on port range. This is just so that you can play games with someone else using BitTorrent on the network. This is just to be friendly, this is not for "security".
Trying to filter all BitTorrent traffic at the gateway is very a difficult problem and a VPN or another type of tunnel can always be used to undermine this kind of filter.