From http://www.w3schools.com (Copyright Refsnes Data)

WSDL Ports

A WSDL port describes the interfaces (legal operations) exposed by a web service.

WSDL Ports

The <portType> element is the most important WSDL element.

It defines a web service, the operations that can be performed, and the messages that are involved.

The port defines the connection point to a web service. It can be compared to a function library (or a module, or a class) in a traditional programming language. Each operation can be compared to a function in a traditional programming language.

Operation Types

The request-response type is the most common operation type, but WSDL defines four types:

Type	Definition
One-way	The operation can receive a message but will not return a response
Request-response	The operation can receive a request and will return a response
Solicit-response	The operation can send a request and will wait for a response
Notification	The operation can send a message but will not wait for a response

One-Way Operation

A one-way operation example:

<message name="newTermValues">
   <part name="term" type="xs:string"/>
   <part name="value" type="xs:string"/>
</message>

<portType name="glossaryTerms">
   <operation name="setTerm">
      <input name="newTerm" message="newTermValues"/>
   </operation>
</portType >

In this example the port "glossaryTerms" defines a one-way operation called "setTerm".

The "setTerm" operation allows input of new glossary terms messages using a "newTermValues" message with the input parameters "term" and "value". However, no output is defined for the operation.

Request-Response Operation

A request-response operation example:

<message name="getTermRequest">
   <part name="term" type="xs:string"/>
</message>

<message name="getTermResponse">
   <part name="value" type="xs:string"/>
</message>

<portType name="glossaryTerms">
  <operation name="getTerm">
      <input message="getTermRequest"/>
      <output message="getTermResponse"/>
  </operation>
</portType>

In this example the port "glossaryTerms" defines a request-response operation called "getTerm".

The "getTerm" operation requires an input message called "getTermRequest" with a parameter called "term", and will return an output message called "getTermResponse" with a parameter called "value".