TCP's congestion control algorithm is mostly reactive, while UTP aims to be predictive. What this basically means is that all the TCP connections that Bittorren

TCP's congestion control algorithm is mostly reactive, while UTP aims to be predictive. What this basically means is that all the TCP connections that Bittorrent opens up are all pushing the network to failure before backing off, and given how many connections Bittorrent makes, wreaks havoc on your quality of service. UTP on the other hand will attempt to predict the congestion control limits, and (I'm guessing) play nicely and slowly reach up to that limit.