Real World XML Web Services: For VB and VB .NET Developers

4.2. WSDL Overview

Figure 4.3 shows one client invoking a Web service using SOAP and another invoking the same service using HTTP GET. Figure 4.4 shows the same process with the various pieces labeled with WSDL terminology.

Figure 4.3. Two clients invoking a Web service. Client A is using SOAP over HTTP while client B is using HTTP GET.

Figure 4.4. WSDL terminology labeling the various parts of a client-service interaction

In WSDL, a service exposes groups of operations (methods). Each group of operations is called a portType, which is roughly analogous ...