QoS-Driven Transactional Web Service Reselection for Reliable Execution

One of the advantages of Web service technology is it can create added-value services and complete the complex transactions or workflows by combining existing ones. However, they always run in a highly dynamic and change environment, during the execution process, if one component service fails or becomes overloaded, the failed services replacing mechanism is needed to ensure that the running process is not interrupted. Towards traditional service adaptive mechanism unreliable for lacking transaction support, this paper proposes a QoS-driven transactional service reselection model for reliable replacement. The model reselects web services not only according to their QoS characteristics but also to their transactional properties. Furthermore, a new comprehensive, objective service reselection utility function over QoS with transactional risk is presented, and the self healing algorithm is proposed. Experiments show that the model guarantees business process reliability.