Abstract

SOAP's place in the web services technology stack is as a standardized packaging protocol for the messages shared by the applications. It uses Extensible Markup Language (XML) as the mechanism for information exchange. Since Web protocols are installed and are available for application by all major operating system platforms, HTTP and XML provide an already at-hand solution to the problem of how programs run under different operating systems in a network. SOAP specifies exactly how to encode an HTTP header and an XML file so that a program in one computer can call a program in another computer and pass its information. It also specifies how the called program can return a response. SOAP is XML. That is, SOAP is an application of the XML specification. It relies heavily on XML standards like XML Schema and XML Namespaces for its definition and function. XML messaging is where applications exchange information using XML documents. It provides a flexible way for applications to communicate, and forms the basis of SOAP. All SOAP messages are encoded using XML. In this thesis, web services, SOAP, WSDL and UDDI are discussed. A web service which queries stock quotes from Yahoo! Finance using SOAP under different server platforms (JAVA and ASP) is implemented and compared in this project.