Optical Fiber Bus Protection Network to Multiplex Sensors: Self-Diagnostic Operation

We present a mathematical model for a wavelength-division multiplexed self-healing optical fiber bus network to interconnect an array of sensors. The network uses protection switching to reestablish service after the failure of one or more of its constituent elements. Our model is a matrix-vector formalism that divides the network into blocks. It predicts which wavelengths arrive at the receiver node when damage has occurred in one or more places. We study single and multiple failures within one block, categorizing and tabulating all combinations of surviving wavelengths. In this way, we correlate the received wavelengths with the failure location(s). The network thus provides self-diagnosis, which we define to be the determination of its own sites of failure from network management information, without requiring external resources.