A petri net semantics for web service choreography

Many Web service standards of orchestration and choreography are designed to reduce their inherent complexity of composing Web services. Existing standards all remain at the descriptive level, without providing any formal semantics and method for verifying important properties. Web Service Choreography Interface (WSCI) describes the flow of messages exchanged by a Web service which participates in choreographed interactions with other services. Due to many advantages of Petri nets, an extended one is used to formalize WSCI in this paper. We show several nets to represent the activity, process and interface respectively. Our formal model remarkably focuses on the WSCI concept of message exchange and the context which describes the environment. This paper proposes some properties and introduces technique for checking them to ensure its correct deployment.