An apparatus includes a device interface system having a first connector and second connector, each with a respective optical signal path arrangement operatively aligned when the two connectors are in a connected position. The operative alignment allows a base optical signal to be transmitted from the first connector to the second connector. An optical signal modification arrangement is included in the second connector and is operable to provide a predefined modification to the base optical signal to result in an optical ID signal that is transmitted back to the first connector. An identification processing unit associated with the first connector receives an ID input signal corresponding to the optical ID signal and produces an identification output responsive to the ID input signal.