Migrating to Web services - latency and scalability

A common way of deploying Web services is to create proxies that expose the legacy application as a Web service. But when it comes to performance, Web services are facing the same barrage of distrust as any new middleware. Are the critics of Web services right? In this paper we will look at several performance pitfalls that Web services are facing today and at the performance penalties that have to be paid when exposing a legacy application as a Web service. We show results about the latency and scalability of Apache´s implementation of SOAP, compare it with the performance of established middleware such as RMI, and look at end-to-end performance of Web services built on top of existing EJB applications.