In the world of decentralization, distributed hash tables (DHTs) recently have had a revolutionary effect. The chaotic, ad hoc topologies of the first-generation peer-to-peer architectures have been superseded by a set of topologies with emergent order, provable properties and excellent performance. Knowledge of DHT algorithms is going to be a key ingredient in future developments of distributed applications.

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http://www.linuxjournal.com/article/6797/