"There has been a lot of fuss lately about Comcast’s efforts to throttle and interfere with BitTorrent traffic, but they are by no means the only ISP involved in such efforts. Hundreds of larger and smaller ISPs all around the world try to limit BitTorrent traffic on their networks, time to give an overview, the war is on."
"The degree of traffic shaping varies a lot between different ISPs. Some only limit BitTorrent traffic during some times of the day or throttle in specific regions, others take a more aggressive approach and prevent their customers from seeding or even downloading .torrent files. The fact is, all the ISPs listed here have been caught - one way or another - messing with BitTorrent transfers.
BitTorrent throttling is not a new phenomenon, ISPs have been doing it for years. When the first ISPs started to throttle BitTorrent traffic most BitTorrent clients introduced a countermeasure, namely, protocol header encryption. This was the beginning of an ongoing cat and mouse game between ISPs and BitTorrent client developers.
Some people might wonder why ISPs throttle their connection. The argument most often used is that all the BitTorrent traffic on their network slows down other customers’ connections. An argument that makes sense (if it is true), but the real problem is that ISPs tend to be secretive about their throttling efforts. My advice to them, if you decide to limit BitTorrent traffic, be open about it and don’t advertise unlimited bandwidth.
So who are these ISPs? Here’s a brief overview of some of the bad guys, take a look at the Azureus wiki for an regularly updated list of throttling ISPs (worldwide)."
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