Fully decentralized DHT based approach to grid service discovery using overlay networks

Distributed hash table (DHT) is widely used in peer-to-peer networks for its scalability, adaptability, and fault-tolerance in large and dynamic environments. In this paper, we study on the application of DHT for grid service discovery. Grid service is represented by multiple (attribute, value) pairs. The virtual organization (VO) is also self-organized into a 2-dimensional network overlays - one for attributes, and the other for values - as nodes join and publish services in the VO. Service discovery in a VO is firstly directed to the attribute overlay to find the nodes with the discovered attributes, then to the value overlay until the nodes which have the same (attribute, value) are reached. Gateway servers are deployed on the border to interconnect different VO´s. The service discovery request can be redirected to other VO´s in case that there is no provider in the requester´s own VO. Our approach is highly efficient, scalable and quick responsive.