By hiding many of the underlying protocols, the Visual Studio .NET environment makes it very easy for developers to create web services. In fact, even programmers with only a general understanding of SOAP and WSDL will be able to create or use web service.
This chapter took a closer look at SOAP, WSDL, and UDDI. As you learned, SOAP (the Simple Object Access Protocol) defines the network messages that applications and a web service exchange that let the application call the service methods and receive a result.
Throughout this book, each time you created a program that uses a web service, you have used Visual Studio .NET to add a web reference to the remote service by specifying the service’s WSDL entries. WSDL, the Web Service Description Language, describes the methods a web service offers, the parameters each method requires, and the type of value each method returns.
Finally, this chapter examined Universal Description Discovery Integration, which is both a collection of tools and a registry that programmers can use to specify information about the web services they have developed and made available for other programmers to use. Think of the UDDI as a “yellow pages” for web services that exist worldwide. The UDDI registry does not store the web services, but rather, it provides links to the services and specifics about the services’ purpose and functionality.