A Global QoS-Driven Evaluation Strategy for Web Services Composition

Since nonfunctional properties play a more and more import role during the process of Web service composition, the QoS issues for Web service composition have obtained great interest in both research community and IT domain. Yet identifying the consumers´ degree of satisfaction on QoS is a significant but challenging problem. This paper proposes a global QoS driven evaluation strategy for Web service composition on top of some previous work, aiming at improving some previous QoS frameworks. The executions of services are analyzed with the ACP (Algebra of Communication Process, a dialect of process algebra), and then the composite QoS values of a composite service are calculated by the ACP expressions. Finally, for the purpose that the composite service is evaluated via aggregating the criteria values into the degree of consumers´ satisfaction, a synthetic method is formulated for comprehensively estimating the weights assigned to the criteria in terms of the consumers´ preferences.