OPTICAL MULTI-BRANCH COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To overcome the problem such that the operating condition of an entire system is made adverse since control is performed for switching an active system to a reserve system even when the reserve system of slave station devices 2-2 to 2-n is temporarily down when the active system of a slave station device 2-1 is down but the reserve system of the slave station device 2-1 is normal. SOLUTION: A master station device monitors the system switching request of the slave station device and controls system switching of the active system and the reserve system in the slave station device.