21. An optical system as in claim 1 , wherein the subscriber unit further comprises a media access controller and a data flow management controller.
21. An optical system as in claim 1 , wherein the subscriber unit further comprises a media access controller and a data flow management controller. 23. An optical system as in claim 21 , wherein the subscriber unit further comprises a phase modulator, an intensity modulator and a quantum dot-enabled semiconductor amplifier that are fabricated on a same semiconductor substrate.