FastTrack

FastTrack is a peer-to-peer (P2P) that was used by the Kazaa, Grokster, iMesh, and Morpheus file sharing programs. FastTrack was the most popular file sharing network in 2003, and used mainly for the exchange of music mp3 files. The network had approximately 2.4 million concurrent users in 2003. It is estimated that the total number of users was greater than that of Napster at its peak.

The FastTrack protocol and Kazaa were created and developed by Estonian programmers of BlueMoon Interactive headed by Jaan Tallinn, the same team that later created Skype. After selling it to Niklas Zennström from Sweden and Janus Friis from Denmark, it was introduced in March 2001 by their Dutch company Consumer Empowerment. It appeared during the end of the first generation of P2P networks – Napster shut down in July of that year.

There are three FastTrack-based networks, and they use mutually incompatible versions of the protocol. The most popular clients on each are Kazaa (and its variations), Grokster, and iMesh.

For more information about the various lawsuits surrounding Kazaa and Sharman Networks, see Kazaa.

FastTrack uses supernodes to improve scalability.

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