Chapter 1 - What Are Web Services?

Abstract

This chapter discusses Web Services, along with their related technologies, protocols, and standards, such as Simple Object Access Protocol (SOAP), Web Services Description Language (WSDL), Extensible Markup Language (XML), and the XML Schema Definition (XSD) standard. It complements the role of Web Services and the way messages are passed between servers and data sources. The simple Web Services (producers) as well as Web Services (consumers) were created using the .NET Framework and VS.NET to show how the Web Service messaging infrastructure works and how it can be used transparently for the developer. The power of Web Services is due to its foundation in nonproprietary protocols and standards. Web Services would not be as useful if it were not built on XML for defining the data and structure, XSD for defining the structure, SOAP for defining a messaging transport mechanism over the well-established HTTP, WSDL for defining method interfaces in XML, Universal Description, Discovery, and Integration (UDDI, a Web Service discovery mechanism), and DISCO, the Web Service discovery description document.