Fiber Fault Management and Protection Solution for Ring-and-Spur WDM/TDM Long-Reach PON

In this paper, a network fault management and protection system for the ring-and-spur long-reach passive optical network (LR-PON) is proposed. We exploit an adapted, enhanced performance, and inexpensive passive optical components in the field and electronic switches in the central office (CO). Our system allows detecting and localizing not only faulty segments but also faulty nodes, hence alleviating the false alarm probability encountered in previous systems. We show that using ring duplication protection in LR-PON can save half the cost compared to full duplication protection with relatively high reliability performance (99.972%). We describe the implementation strategy of our system in several well known metro network topologies including: (1) single ring, (2) double ring and (3) double fiber pair based ring. The architecture of the remote nodes and the central office is described in addition to the appropriate placement of the passive monitoring devices. We derive an expression for the upper bound notification and recovery times. Moreover, we found that our system can recover from a fault in about 0.5ms as an upper bound.