J2EE™ Security for Servlets, EJBs and Web Services: Applying Theory and Standards to Practice

Chapter 11. Web Service Security

A Web service is a program that has a message-based interface described in a WSDL (Web Service Description Language) document. A WSDL description is somewhat similar to a CORBA IDL (Interface Definition Language) description, in the sense that it describes the interface of a network service. A WSDL document defines a set of end-points operating on messages. The operations and messages are described abstractly, and then bound to a concrete network protocol, such as HTTP, and a message packaging format, such as SOAP (Simple Object Access Protocol), to define a binding. The combination of a binding and a network address makes a concrete endpoint, also known as a port. A Web service is simply a collection of ports. ...