To provide efficient monitoring of web service-based business processes, a web service proxy （WS- proxy） is developed to monitor business activities by monitoring the enactment of services. WS-proxy is deployed as an intermediary between internal business processes and external service providers, and it provides a single point of service access with the functions of message routing and content inspection. By using an XPath engine named WS-filter, performance indicators can be generated from service messages for assessing business performance. In the experiments, the feasibility of WS-proxy is verified and it achieves good performance in the monitoring work. The latency introduced by WS-proxy is only about 15% of the overall latency while extracting performance indicators just consumes less than one third of the processing time.
