Bittorrent traffic not using the P2P queue

Bittorrent is known for not using standard ports. Clients are allowed to declare which port other clients use to reach them, which means chaos for network administrators trying to track the traffic based on port alone. Clients can also choose to encrypt their traffic. Regular shaper rules don’t have any way to examine the packets to tell what program the traffic appears to be, so it is forced to rely on ports. This is why it may be a good idea to use the P2P Catchall rule, and/or make rules for each type of desirable traffic and treat the default queue as low priority.