A Fast and Scalable Mechanism for Web Service Composition

In recent times, automated business processes and web services have become ubiquitous in diverse application spaces. Efficient composition of web services in real time while providing necessary Quality of Service (QoS) guarantees is a computationally complex problem and several heuristic based approaches have been proposed to compose the services optimally. In this article, we present the design of a scalable QoS-aware service composition mechanism that balances the computational complexity of service composition with the QoS guarantees of the composed service and achieves scalability. Our design guarantees a single QoS parameter using an intelligent search and pruning mechanism in the composed service space. We also show that our methodology yields near optimal solutions on real benchmarks. We then enhance our proposed mechanism to guarantee multiple QoS parameters using aggregation techniques. Finally, we explore search time versus solution quality tradeoff using parameterized search algorithms that produce better-quality solutions at the cost of delay. We present experimental results to show the efficiency of our proposed mechanism.