Fault tolerant PON topologies

The authors propose a redundant, tree structured passive optical network (PON) configuration which can withstand all single and most double link failures. The redundant configuration results from the superposition of two physically separate, diverse-routed trees. This redundancy is transparent to the user. It does not require switching elements or special controls inside the network. It permits easy identification of the fault by the network control center. The fault tolerance properties of the proposed solution are evaluated. Power budget, fiber installation cost, and metropolitan coverage issues are investigated.<
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