That's basically how you do it. Torrent packets have a certain "signature" (you can usually even determine the client from this, even if all traffic is encrypte

That's basically how you do it. Torrent packets have a certain "signature" (you can usually even determine the client from this, even if all traffic is encrypted). That, and torrent traffic is pretty leaky... even if you are encrypting, not all of your peers are.