An Efficient Resource Discovery while Minimizing Maintenance Overhead in SDDS Based Hierarchical DHT Systems

Using Distributed Hash Tables (DHT) for a resource discovery in large-scale systems generates considerable maintenance overhead which affects the routing efficiency. In this paper, we propose a hierarchical DHT solution based on scalable distributed data structures (SDDS) for an efficient resource discovery in data Grids. Our solution deals with a reduced number of gateway peers running a DHT protocol. Each of them serves also as a proxy for second level peers in a single Virtual Organization (VO), structured as an SDDS. We present a cost analysis for a resource discovery process and discuss its capabilities to reduce both lookup and maintenance costs while minimizing the overhead added to the system. The analysis results proved that an SDDS based hierarchical DHT solution offers good performances especially for intra-VO resource discovery queries. They also provide significant system maintenance saves especially when peers frequently join/ leave the system.