BitTorrent is the name of a peer-to-peer (P2P) file distribution protocol, and is the name of a free software implementation of that protocol. The protocol was originally designed and created by programmer Bram Cohen, and is now maintained by BitTorrent Inc. BitTorrent is designed to distribute large amounts of data widely without incurring the corresponding consumption in costly server and bandwidth resources. CableLabs, the research organization of the North American cable industry, believes that BitTorrent represents 55% of the upstream traffic on the cable companies’ access network.CacheLogic puts that number at roughly 35% of all traffic on the Internet, although there are dissenting opinions on the methodology to measure P2P traffic on the Internet.
An interactive Java Applet showing how the BitTorrent network works. The image below consists of 5 seeders and 5 leechers.
BitTorrent source Wikipedia