wsdl

wsdl is a specifaction defining how to describe web services in a common xml grammar. wsdl desribes four critical pieces of data: interface information describing all publicly avaiable functions; data types information for all messages requests and message response, binding information about the transopot protocol to be used. address information for locationg the specified service.

it defines the name of the message and contains zero or more message part elements which can refer to message parameters or message return values.

 

the porttype element combines multiple message elements to form a complete one-way or round-trip operation. the bingding element describles the concrete specifies of how the service will be implemented on the wire. wsdl includes built-in extensions for defining soap services and soap -specific information. the service element defines the address for invoking the specified service.

 

the binding element provides specific details on how a porttype operation will actually be transimitted over the wire.