摘要

Web service is an important technology for constructing distributed applications. In order to provide more complex functionalities, services can be reused by applying service composition. A service composition can be designed and implemented through a centralization or decentralization strategy. When observing the decentralized service composition, several researchers found out that this kind of compositions has its own advantages. These findings promote the development of approaches for designing, implementing and applying decentralized service compositions. Process partitioning is a topic about dividing a process into a collection of small parts. The technique is applicable to partitioning a process in a centralized service composition, and the result can provide support to constructing a decentralized service composition. This paper presents a technique of process partitioning. The technique can be used for constructing decentralized service compositions, and it provides a graph transformation based approach to reorganizing a process which is represented as a process structure graph. Compared to existing approaches, the technique can partition well-structured and unstructured processes. Some issues about decentralized service compositions and performance tests of service compositions are discussed in this paper. Experimental results show that, when compared with the centralized service composition, the decentralized service composition can have lower average response time and higher throughput in runtime environment.