Client-side binding stubs support a simple programming model for Web services. The binding stubs are automatically generated by tools from each Web service's WSDL description, and provide a local interface for each remote Web service.
Direct calls (without the use of binding stubs) to Web services are slightly more complicated, but incur significantly less overhead. There is no need to generate or maintain binding stubs for each Web service, and direct calls support dynamic invocations.
The basic Web services infrastructure, comprising SOAP, WSDL, and UDDI, provide a good platform for industry-standards-based XML messaging between applications. However, this basic platform does not support additional enterprise-class requirements such as support for mobility, transactions, workflow, and security. (See the next chapter for how to implement an enterprise application that supports these requirements.)