P-Ring is a new peer-to-peer (P2P) index structure. This paper introduces and describes this fully distributed, fault-tolerant structure that provides load balancing and logarithmic search performance while supporting both equality and range queries.

The authors describe the model and architecture in detail, and present pseudocode algorithms. They also document the testing results and performance analysis. The authors conclude that “P-Ring outperforms [most of the] existing index structures[, and ...] that it maintains its excellent search performance with low maintenance cost in a dynamic P2P system.”

I recommend this paper to anyone interested in P2P systems and their application.