Web Service Discovery in Large Distributed System Incorporating Semantic Annotations

Web services are the new paradigm for distributed computing. A critical factor to the overall utility of Web services is a scalable, flexible and robust discovery mechanism. Traditional centralized indexing scheme can’t scale well with a large distributed system. In this paper, we first use an ontology-based approach to capture real world knowledge for semantic service annotation. Then we use a distributed hash table (DHT) based catalog service in P2P system to index the ontology information and store the index at peers. We have discussed the DHT based service discovery model and discovery procedure. The solution to system evolution is proposed. However, DHT supports only exact match lookups, we have made improvement to the matching algorithm for flexible service discovery. The experiments show that the discovery model has good scalability and the semantic annotation can notably improve discovery exactness. The improved algorithms can discover the most potential service against request.