Optical communication service

A method of receiving at a first communication subsystem a message from a second communication subsystem, the method comprising:

• storing, in memory of the first communication subsystem, a look-up table comprising a plurality of entries, wherein each entry comprises a unique message and a unique optical detection;
• after the storing, detecting, with an optical sensor assembly of the first communication subsystem, optical signals from the second communication subsystem during a state change of the second communication subsystem;
• generating, with the optical sensor assembly of the first communication subsystem, optical data based on the detected optical signals;
• identifying, with the optical sensor assembly, a particular entry of the plurality of entries whose unique optical detection matches the generated optical data;
• and
• controlling, with the first communication subsystem, a functionality of a managed element of the first communication subsystem based on the unique message of the identified particular entry.