Failure prediction and failure isolation in fiber optic systems are of extreme importance in aircraft, where a delay of microseconds in conveying a warning of failure may cause critical loss. Existing systems attempt to address this problem by using conventional techniques such as error correction coding, serial control insertions, block pre- or post-ambles.... These approaches sacrifice critical speed, result in loss of modularity, and have problems of interface component reliability. The result is a significant loss in efficiency and increase in cost. Optical communications corporation (OCC) proposes a fiber optic innovative system, elegant in its simplicity, solving the reliability problems, while being completely compatible with existing standards. The built-in-tet (bit) circuitry of the proposed system encompasses an error detection code overlaying each bit, and it has an ability to deliver self-test information quickly to the next channe in-band. The bit error rate (BER) of the system is reduced significantly. Additionally, the system can overcome a catastrophic failure without becoming inoperative, and users at the far end can be notified concurrently with receipt of the data itself.
