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

Web services, the new way of stitching data and processing resources together to form elaborate, distributed applications, aren't like other software systems. They differ even from other architectures for distributed applications. In his fantastic Understanding Web Services, Eric Newcomer helps his readers figure out what Web services are all about. This book is better than any other book out there in helping readers come to grips with the terms, technologies, behaviors, and design requirements that define the Web services universe. It's remarkably light on code--Newcomer's logic appears to be that you should dig into the details of implementation only after you thoroughly understand the design concepts--and emphasizes definition and exposition of SOAP, UDDI, WSDL, and ebXML.

Newcomer's work looks and reads almost like a notebook, with succinct statements in the margin (for instance, "SOAP processors first have to check the mustUnderstand attribute, if any"), adjacent to paragraphs that go into greater depth. He's careful to call attention to differences among the relevant standards documents, and points out differences among implementations. Graphical learners may wish for more conceptual diagrams, as there aren't a lot of them here. Newcomer's prose is brilliant, though, and it's pretty easy to determine what he means. Perhaps best of all, Newcomer isn't cheap with his opinions and forecasts. It's helpful to read his informed feelings and predictions. --David Wall

Topics covered: The specifications, implementations, and popular trends that define the Web services movement. Conceptual coverage of Extensible Markup Language (XML), Simple Object Access Protocol (SOAP), Web Services Description Language (WSDL), and the Universal Description, Discovery, and Integration (UDDI) protocol fills these pages. Emphasis is on how it all works rather than on how to program for it.