PON (PASSIVE OPTICAL NETWORK) SYSTEM AND COMMUNICATION DEVICE

摘要

PROBLEM TO BE SOLVED: To enhance reliability of communication.SOLUTION: A PON system has a first PON where a communication device is connected with a plurality of upper terminators, and a second PON where the communication device is connected with a plurality of lower terminators. The communication device has a communication unit communicating with any one of the plurality of upper terminators via any one of a plurality of optical transmission paths connecting the plurality of upper terminators and the communication device, and a changeover unit for switching the optical path used by the communication device to any one of a plurality of optical paths depending on the fault state.SELECTED DRAWING: Figure 1