Understanding Web Services - XML, WSDL, SOAP, and UDDI

Web services enable the new generation of Internet-based applications. These services support application-to-application Internet communication--that is, applications at different network locations can be integrated to function as if they were part of a single, large software system. Examples of applications made possible by Web services include automated B2B transactions, as well as desktop and handheld devices client access to reservation and order-tracking and the like.

Several key standards have emerged that together form the foundation for Web services: XML (eXtensible Markup Language), SOAP (Simple Object Access Protocol), UDDI (Universal Description, Discovery, and Integration), and WSDL (Web Services Definition Language). In addition, ebXML (Electronic Business XML) has been developed recently to facilitate automated business process integration among trading partners.

This book introduces the main ideas and concepts behind core and extended Web services technologies and provides developers with a primer for each of the major technologies that have emerged in this space. In addition, Understanding Web Services summarizes the major architectural approaches to Web services , examines the role of Web services within the .NET and J2EE communities, and provides information about major product offerings from Microsoft, IBM, IONA, HP, Sun, BEA, Oracle, and others.

Key topics include:

• XML facilities for structuring and serializing data
• How WSDL maps services onto communication protocols and transports
• WSDL support for RPC-oriented and document-oriented interactions
• SOAPs required and optional elements for Web services
• Message processing and the role of intermediaries in SOAP
• UDDI data formats
• SOAP APIs used to store and retrieve information from UDDI

How ebXML offers an alternative to Web services that supports reliable messaging, security, and trading partner negotiations With Understanding Web Services, you will be well informed and well positioned to participate in this vast, emerging marketplace.

Contents

• 1. Introducing Web Services.
• 2. Describing Information—XML.
• 3. Describing Web Services—WSDL.
• 4. Accessing Web Services—SOAP.
• 5. Finding Web Services—UDDI Registry.
• 6. An Alternative Approach—ebXML.
• 7. Web Services Architecture—Additional Technologies.
• 8. Implementing Web Services.