Prefix Hash Tree

Distributed Hash Tables are scalable, robust, and self-organizing peer-to-peer systems that support exact match lookups. This paper describes the design and implementation of a Prefix Hash Tree - a distributed data structure that enables more sophisticated queries over a DHT. The Prefix Hash Tree uses the lookup interface of a DHT to construct a trie-based structure that is both efficient (updates are doubly logarithmic in the size of the domain being indexed), and resilient (the failure of any given node in the Prefix Hash Tree does not affect the availability of data stored at other nodes).
Paper: http://berkeley.intel-research.net/sylvia/pht.pdf