Flexible information discovery in decentralized distributed systems

The ability to efficiently discover information using partial knowledge (for example keywords, attributes or ranges) is important in large, decentralized, resource sharing distributed environments such as computational grids and peer-to-peer (P2P) storage and retrieval systems. This paper presents a P2P information discovery system that supports flexible queries using partial keywords and wildcards, and range queries. It guarantees that all existing data elements that match a query are found with bounded costs in terms of number of messages and number of peers involved. The key innovation is a dimension reducing indexing scheme that effectively maps the multidimensional information space to physical peers. The design, implementation and experimental evaluation of the system are presented.

1. Introduction

The recent years have seen an increasing interest in two resource sharing environments: Peer-to-Peer (P2P) computing and Grid computing. Emerging from different communities, they have a common final objective: to pool and coordinate large sets of resources [5].