An optical device (100) for an optical network, comprising an optical input (110), a passive optical component (112), a memory device (114) for storing information relating to the passive optical component. The optical device further comprises an optical splitter (116) configured to power split off a portion of received optical signals to form split optical signals and to output the remaining optical power of received optical signals to the passive optical component and a photodetector (118) configured to receive the split optical signals and to generate a corresponding photodetector output signal. Further the optical device comprises an accumulator (120) configured to be charged by the photodetector output signal, a laser (122) configured to be powered by the accumulator and a controller (124) configured to, in response to a trigger from the photodetector, read said information from the memory device and to cause the laser to transmit an optical signal from an optical output (110), the optical signal carrying a message based on said information read from the memory device.