Correlation-aware web services composition and QoS computation model in virtual enterprise

When establishing a virtual enterprise (VE), how some enterprises with different resources and advantages form the alliances by providing respective services to compose the VE for certain profits, it is actually a process of services composition. There always exist a lot of web services with similar functions but different non-functionality properties in the process of web services composition. In order to enhance the quality of service composition, non-functionality properties, i.e., quality of service (QoS) are usually considered. However, most existing works about QoS-based service composition treat the services involved in composition as independent from each other, and their correlations are usually ignored. In fact, most services have some correlations with each other, and the correlations can affect the whole quality of service composition badly. In this paper, three kinds of correlations in services composition are investigated, and a correlation-aware QoS model is studied. The impact of each kind of correlation on the whole QoS of services composition is investigated. A case study indicates that higher quality of services composition can be achieved when considering the correlations among composite services.