TWSO - Transactional Web Service Orchestrations

There is a need for transactional processing in the Web service world. Software industry responded to this need by publishing a couple of Web service transaction proposals that are quite alike. However, these proposals define basically only communication protocols that indirectly implement advanced transaction models. The proposals lack accurate usage suggestions and the rather obvious question “How can I use transactions in Web service based distributed systems?” is not covered anywhere satisfyingly. The use of arbitrary advanced transaction models is provided only by some of the proposals and likely requires an update of various transaction system components. This paper introduces TWSO (Transactional Web Service Orchestrations), a new approach to integrate transactional processing with Web service orchestrations. It tries to overcome the hassles stated above. TWSO concepts may appear in different manifestations, like an XML vocabulary (TWSOL) or an API for Java (TWSO4J). Constructs of TWSO manifestations are intended to be directly incorporated in Web service orchestration definitions. The usage pattern of TWSO is designed to resemble the programming pattern used when application programmers use transaction–enabled components like databases or application servers. Moreover, arbitrary advanced transaction models can be synthesized by using a basic set of transaction primitives without the demand for system–updates.