First and second optical fibers carry information modulated on an optical
carrier. Information modulated on the carrier is to be recovered and
transmitted at a first node along the first and second optical fibers.
The first node includes apparatus for receiving and transmitting the
information. The apparatus for receiving and transmitting the information
includes a first receiver for demodulating the information modulated on
the optical carrier and carried on the first optical fiber, a second
receiver for demodulating the information modulated on the optical
carrier and carried on the second optical fiber, a transmitter for
modulating the information on the second optical fiber, and a splitter
for splitting the optical carrier carried on the first optical fiber. The
splitter is coupled to the first optical fiber and the first receiver. A
portion of the optical carrier is coupled to the first receiver and
another portion of the optical carrier continues on the first optical
fiber.