Signaling Free Localization of Link and Node Failures in an Optical Mesh-Tree Network

A monitoring mechanism combining the advantages of a monitoring trails scheme and an optical coding scheme is proposed; the mechanism can be used in a metro-access network. Optical encoders are centrally placed in an optical distribution network and at both sides of each remote node, which makes for much simpler installation and smaller management costs. A modified heuristic monitoring trail allocation algorithm is used for monitoring the inner links of the mesh network. The principle of the complete monitoring scheme and various fault scenes are displayed. The results show that the designed monitoring mechanism costs less and is easily scalable. This system can monitor not only the states of fiber links but also nodes in the network to alleviate the false alarm probability. It can also support high network capacity. Moreover, it can take a trade-off of the number of monitors and optical encoders.