Runtime Service Discovery for Grid Applications

Abstract

This chapter describes a framework to support runtime service discovery for Grid applications based on service discovery queries in both push and pull modes of query execution. The framework supports six different types of trigger conditions that may prompt service replacement during run-time of grid business application, and evaluates the relevance of a set of candidate services against service discovery queries. The chapter also describes the language used to express service discovery queries and the three types of fitness measurement used to evaluate the candidate services against these queries. Both synchronous (pull) and asynchronous (push) mechanisms for service discovery are presented and shown to be complimentary in dealing with all six service discovery trigger conditions. The chapter is illustrated through examples.