Proactive adaptation of service composition

Adaptation of service compositions is considered a major research challenge for service-based systems. In this paper we describe a proactive approach to support adaptation of service compositions triggered by different types of problems. The approach allows for changes in the composition workflow by replacing a service operation, or a group of operations, by another service operation or a group of dynamically composed operations. The adaptation process is supported by the use of QoS prediction techniques, analysis of dependencies between service operations, and use of groups of service operations in a composition flow instead of isolated operations. A prototype tool has been implemented to illustrate and evaluate the framework. We also present results of experiments that we have conducted to evaluate the work.