The client can be invoked in session or offline mode. Usually a user wants to use the client in session mode, which means that he or she joins a session from the list of running sessions.
But it is sometimes useful to run the client without having a connection to the server. In offline mode, the session is created locally instead. In this case, there is no login and no discussion window. This is usefull if the application should be used for plain image processing without having contact to other users.
Standard invocation: java gipp.Client
Offline invocation: java gipp.Client -offline