A digital data processor of the type used, e.g., in management of a storage area network (SAN), executes a process (a "manager" process) to maintain a representation of the SAN topology or at least an attribute thereof. A graphical output device displays the SAN representation. A further process (a "user interface" process) controls the output device for purposes of displaying that representation. An interface element effects retrieval of the SAN representation, for example, in response to a request from the user interface process. It transmits that representation to the user interface process for display on the graphical output device.