3. Communal systems
Some abuse comes from communal systems, for instance those in a computer room or library. To determine who was using the system at a particular time, the system should require authentication before use, ideally with logs stored on a separate machine. In the case of "kiosk-mode" terminals where the functionality is severely restricted, it may be appropriate to allow usage without authentication. However if general access is permitted (for instance, access to arbitrary websites) then we would strongly recommend that adequate authentication and logging measures are in place.