This behaviour requires enter and exit use cases. We assume that other functionality is only available once the enter use case has been carried out and the user has logged in. Many systems will wish to offer a guest login as well as a member login. The user enters an authenticated session and is presented with a tailored information landscape. User provides user-name and password.
New session is started and initial information landscape is displayed based on user profile.
The Enter scenario may be initiated by the system if the user attempts to access a service that requires authentication. User may select guest access instead of providing a user-name and password for member access. If so, features that require users to be authenticated will not be available or functionality will be limited. If the Enter scenario was initiated when a user tried to access a service that requires authentication then they will be returned to the service they were attempting to access after a successful authentication. Continue an existing session rather than starting a new one, and then display information landscape based on existing session.