Abstract: A method, apparatus and system for the communication of services in an optical access network includes transmitting services to customer premises using a passive optical downstream link and receiving services from said customer premises using an active optical upstream link. In an embodiment of the present invention, services from a central office are communicated to customer premises using a passive means for splitting an optical signal, and services from customer premises intended for the central office are communicated to the central office using active components including at least one receiver, a switch and a transmitter.

Abstract: An optical access network employs a ring topology in which connections between the network units and between the network units and the optical line terminal are via a protection switch. The protection switch monitors connections from the optical network units to detect a loss of signal and, on detecting a loss of signal from an optical network unit, switches the respective optical network unit out of the ring, thus maintaining continuity of the ring topology.