Analyses of QoS-Aware Web Services

Abstract

Quality-of-Service (QoS) in Web services considers a service’s non-functional characteristics during service advertisement, discovery and composition. In this paper, we analyze the requirements of QoS-aware Web services and present the corresponding findings as well. We firstly propose a common set of QoS attributes with formal definitions to encourage the creation of a general QoS model for Web services. Based on the attributes, we define the process of QoS-aware service discovery and two alternative matching criteria namely absolute and relative matchmaking are discussed to enable flexible service selection. Finally, we present the aggregative effects of QoS attributes according to the formal semantics of different workflow patterns to help service consumer perform QoS-aware service composition.