Definition: Kazaa

An earlier subscription-based online music service from Brilliant Digital Entertainment, Inc., Sherman Oaks, CA. For a monthly fee, Kazaa provided unlimited downloads of music for playing on up to three PCs. An unlimited number of ringtones were also available for one cellphone. In 2012, the service was discontinued.

An Infamous Beginning
The original "KaZaA" was a file sharing service founded in 2001 in Amsterdam by Niklas Zennstrom and Janus Friis, who created the underlying FastTrack peer-to-peer technology that was also used to power other services such as Morpheus and Grokster. Within two years, Kazaa claimed a record 230 million downloads.

Supported by advertisers, the Kazaa Media Desktop software enabled users to view paid content from Altnet as well as content from other users, the latter seriously vexing the music publishing companies. Although users were encouraged to not share copyrighted material, most downloads violated copyrights. The music industry sought to close down the company, and a Dutch court ordered the cessation of the Kazaa software. However, because the Kazaa system was totally distributed, existing users could still swap files, and people still continue to swap music using programs such as Kazaa Lite and Kazaa Resurrection, although to a significantly lesser degree.

In 2002, the Kazaa website and logo were sold to Australian Sharman Networks Ltd. Four years later, Sharman paid $100 million to settle music industry lawsuits and agreed to turn Kazaa into a legitimate service. Brilliant Digital Entertainment (BDE), an Altnet owner, partnered with Sharman to create legal downloads that include digital rights management (DRM). See peer-to-peer network, Napster and BitTorrent.

The Kazaa Supernode Architecture
Unlike Napster, which provided a central directory of shared files, the original Kazaa distributed its directories to "supernodes," which were the users' own computers. Supernodes communicated with other supernodes to complete a search. Users with fast computers and connections were automatically made supernodes unless they disallowed it. As a supernode, no more than 10% of the CPU power was used.

File swapping systems have been architected in different ways as outlined in the following illustrations: