title: Can I use WCF duplex binding to relay message?
body: <p>I have a Client Application, a server and another client, lets call it third party. I have a callback interface as part of my contract that is implemented both by the third party and the client. </p>
  
  <p>The third party will call a server operation(method) then the server will trigger a callback but instead of calling the callback of the third party, it will call the callback implementation of the client. </p>