تکنیک مبتنی بر شبکه پتری برای ساخت ترکیب سرویس قابل اعتماد

Service composition is an important mean for integrating the individual Web services to create new value added systems that satisfy complex requirements. However, it is challenging to guarantee the reliability of service composition in a distributed, dynamic and complex environment. This paper proposes an approach to constructing the reliable service composition. The underlying formalism is Petri net, which provides means to observe behaviors of basic component, and to describe their interrelationship. The transaction attributes, reliability and failure processing mechanisms are articulated. The composition mechanism systematically integrates these schemas into a transaction mapping model. Based on this, a reliable composition strategy and its enforcement algorithm are proposed, which can verify the behaviors of service composition at design time or after runtime to repair design errors. The operational semantics and related theories of Petri nets help prove the effectiveness of the proposed method. Finally, we use a simplified Export Service system to demonstrate the feasiability of the method.