A Performance Model for the Web Service Protocol Stacks

Web services are built on XML. They use XML for describing the service interface, they use XML for message exchange and the WS-* protocols that provide addressing, security and reliable messaging also use XML. This burdens the communication with a large response time overhead compared to binary distributed communications like CORBA or RMI. Therefore, it is important to know how to design the interface of a web service so we can minimize the communication overhead. In this paper we propose a performance model with which the response time overhead of web services with arbitrary interfaces can be predicted if the coefficients of the model are calculated from some simple measurements for the given set of test cases. The paper shows the measurement results for two web service frameworks and also gives a detailed description of the performance model.