As of 1.9. Unique ID of the luminaire the light is a part of in the format: AA:BB:CC:DD-XX-YY. AA:BB:, ... represents the hex of the luminaireid, XX the lightsource position (incremental but may contain gaps) and YY the lightpoint position (index of light in luminaire group). A gap in the lightpoint position indicates an incomplete luminaire (light search required to discover missing light points in this case).