Abstract: The present invention is a self-calibrating n.times.m optical routing switch which is controlled by a microprocessor to operate when signal condition degrades beyond user-definable thresholds. Preferably, the optical routing switch is a 2.times.2 or 1.times.2 device with an optical switch isolator to minimize crosstalk. In other embodiments, the optical routing switch output comprises the RF modulation carried by the input optical signal or the optical fiber input comprises a plurality of carrier wavelengths. A microprocessor compares real-time signal quality to a standard value and operates the switch when signal quality falls below a threshold value. Depending on the desired characteristics of the optical routing switch, the microprocessor controlled switch may comprise an optical switch, an optical switch isolator coupled to an optical switch, an optical switch isolator coupled to a wave division multiplexer, or an RF switch.