Abstract: A fiber optic bidirectional communications network includes a plurality of decentralized communication nodes each including a receiver for receiving electromagnetic radiation at a wavelength ?2 and a transmitter for transmitting electromagnetic radiation at a wavelength ?1, at least one relay including a receiver operable to receive signals at ?2 and a transmitter for transmitting signals at ?2. At least one passive optical network (PON) includes at least one optical fiber, at least bidirectional coupler coupled to the optical fiber for coupling signals at ?2 transmitted by the relay to the plurality of communication nodes and for combining signals at ?1 from the plurality of nodes into the optical fiber for coupling to the relay. Any of the plurality of communication nodes may communicate of the other communication nodes via the relay. In one embodiment ?1??2 and the relay is a wavelength shifting relay.