Web process dynamic stepped extension: Pi-calculus-based model and inference experiments

Web Processes combine traditional workflow management with Web Services technology. A key challenge to support dynamic composition of Web Processes is to solve the conflicts between process deployment and process execution caused by the inner dependencies. To address this, we have presented a dynamic extension pattern, termed the Web Process Dynamic Stepped Extension (WPDSE). In this approach the process is divided into multiple sub processes, and each sub process is defined and deployed at different times during process execution based on the requirements. A rigorous mathematic modeling language, pi-calculus, is used to define the framework and extension units of the WPDSE. The primary benefit derived from using the pi-calculus is that both the correctness and dynamic performance of the WPDSE model can be effectively verified and analyzed using a mathematically sound approach. This is done using a pi-calculus inference prototype tool called the Interactive Inferring Tool (InferTool).