Web Service Composition Transaction Management Research

Web services technology solves the problem of interaction between information systems, and promotes the development of B2B(Business to Business) and EAI(Enterprise Application Integration). But for commercial applications, reliability and consistency are the most basic requirements. Therefore, Web services transaction management technology becomes to be the core of the problem that Web services technology is widely used, and becomes to be the research focus in the Web services field.Web service is autonomy, inter-regional, long-running, as well as transaction initiator and service providers have their own interests and goals. The above reasons lead to that the traditional transaction management does not apply to Web services transaction management. However, existing Web services transaction management specification only gives the basic coordination function, but does not give a solution to the following two questions:(1) How to reduce the cost of the failure of Web services composition and the times of non-compensable web services needing to be compensated.(2) How to guarantee transaction initiator and service providers'the interests, that is to say how to prevent transaction initiator to cancel the transaction arbitrarily and service providers to quit from the transaction arbitrarily.In response to these two issues, this paper introduces the basic concepts of transaction management, analyzes the basic transaction management technology, extended transaction management technology and the existing Web services transaction management specification firstly. And then focuses on the first question, based on analysis of forward recovery, backward recovery and non-compensation, define the cost of failure risk,and provide a scheduling algorithm named WSDSA(Web Services Dynamic Submit Algorithm) based on web services time constraints and the cost of failure risk, WSDSA ensures web services to meet time constraints and postpones web services which have big cost of failure risk or can't be compensated to submit. Simulations show that compared with traditional methods, WSDSA reduces the failure cost of web services composition and times of non-compensable web services needing to be compensated. For the second problem, we give the contract-based transaction management technology.This paper combines the Web services transaction scheduling algorithm based on the cost of failure risk and the contract-based transaction management technology, gives the overall function of long transaction coordination framework and introduces the design and implementation of abstract service, adapter, improved Ws-Coordination protocol(including Contract Service), coordinator management and participant.