A Formal Model of Service Network and Its Description Using Pi-calculus

The concept of service network really helps to achieve dynamic, flexible, self-service composition. Service network is composed of nodes. The channel structure of nodes reflects the interaction between services and the dynamic structure of service composition. Besides a brief review and summary of the recent research of service composition and the formal description of interface, this paper defines the abstract service, service and the channel between them as the basic of service network. The definition of abstract service and service is given through the formal description of the syntax and semantic structure of channel. The relationship between channels is defined upon the definition mentioned above. All of the concept mentioned above can be described by Pi-calculus, and the validity of them is explained through an example at the end. The formal model presented in this paper provides the theoretical foundation for several works that base on service network, such as the dynamic service composition, the authentication of the correctness and consistency of service composition, and security of service composition.