SPEWS: A Framework for the Performance Analysis of Web Services Orchestrated with BPEL4WS

This paper addresses quality of service aspects of Web services (WS) orchestrations created using the business process execution language for Web services (BPEL4WS). BPEL4WS is a promising language describing the WS orchestrations in form of business processes, but it lacks of a sound formal semantic, which hinders the formal analysis and verification of business processes specified in it. Formal methods, like Petri nets (PN), may provide a means to analyse BPEL4WS processes, evaluating its performance, detecting weaknesses and errors in the process model already at design-time. A framework for transformation of BPEL4WS into generalized stochastic Petri nets (GSPN) is proposed to analyse the performance and throughput of WS, based on the execution of orchestrated processes.