The original BitTorrent client that had at one point set the Internet world on it's ear has received a facelift. This time it addresses issues ISPs have with the amount of traffic dedicated to the BitTorrent P2P network.
A more viable solution is the use of traffic caching. What this technique does is caches popular download paths in internal network servers, thereby making BitTorrent traffic route through internal networks, rather than rely on their external network usage. This allows speeds to remain constant and its much cheaper for ISPs to operate within their internal network.
BitTorrent 4.20 impliments the latter, a traffic caching feature called Cache Discovery Protocol. The feature within the client allows ISPs to detect that the client can understand how to route through cached servers and makes both parties happy.
Source:
Slyck











