Instructions: Start the server by clicking the "Start Server" button. Register (actually a dummy registration) the client by clicking on the "Start" button of the client. Then click the "Update" button, then the "Invite" button. The textareas show the messages being sent between the server and the client. See comments in the client source code for details.
Warning! The code provided above does not deal with the "heartbeat" messages as defined in the protocol document.