# Web Services Description Language (WSDL) reference

A WSDL document defines services as collections of network endpoints, or ports. In WSDL, the abstract definition of endpoints and messages is separated from their concrete network deployment or data format bindings. This allows the reuse of abstract definitions: messages, which are abstract descriptions of the data being exchanged, and port types which are abstract collections of operations.

The concrete protocol and data format specifications for a particular port type constitutes a reusable binding. A port is defined by associating a network address with a reusable binding, and a collection of ports define a service. Hence, a WSDL document uses the following elements in the definition of network services:

- Types: a container for data type definitions using some type system (such as XSD).
- Message: an abstract, typed definition of the data being communicated.
- Operation: an abstract description of an action supported by the service.
- Port Type: an abstract set of operations supported by one or more endpoints.
- Binding: a concrete protocol and data format specification for a particular port type. The binding is usually SOAP and the encoding and data formatting regulations used (also known as the style) is usually literal (this includes document/literal, and sometimes rpc/literal).
- Port: a single endpoint defined as a combination of a binding and a network address.
- Service: a collection of related endpoints.

For more information on WSDL, refer to

www.w3.org/TR/wsdl

The various WSDL elements can be structured in many ways. It can be in one single WSDL file or in mulitple WSDL files. If the IBM® WebSphere® or AXIS 1.0 run-time environment are selected, Rational® Developer products generate one single WSDL file containing in-line schema. If the IBM SOAP run-time environment is selected, Rational Developer products generate multiple WSDL and XSD files by default.

Parent topic: Web Services Description Language (WSDL)

Related Concepts
Web services overview
Web Services Description Language (WSDL)

Related Tasks
Developing Web services
Using the Web Services Explorer

Related Reference
WSDL files generated by the IBM SOAP run-time environment

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