Service-level agreement-based QoS analysis for web services discovery and composition
Stephen J.H. Yang, Jia Zhang, Blue C.W. Lan · International Journal of Internet and Enterprise Management · 2006
Quality-of-Service (QoS) in web services considers a service's non-functional characteristics during service specification, discovery and composition. In order to facilitate the development of QoS-aware web services, we first develop a QoS-aware model, which contains a configurable and extensible set of QoS attributes including response time, throughput, reliability, availability and price. We also examine how to use ad hoc industry standard Service Level Agreements (SLAs) to carry QoS specifications for web services. Then, two alternative service selection methods, namely, absolute and relative matchmaking, are presented to discover candidate services based on the QoS data derived from SLA documents. Finally, according to the formal semantics of workflow patterns, we utilise the aggregative effects of QoS attributes to help perform QoS-aware service composition.