The invention discloses a ring communication network
master station redundancy method, a device and a
system. The method comprises steps: a
backup master station receives and caches a data packet sent by a working
master station adjacent to the network position of the
backup master
station, after a data packet sent by the working master
station in an opposite direction arrives at a target
station, the target station sends a feedback data packet back, and the feedback data packet is eliminated after arriving at the working master station and the
backup master station; the backup master station determines a
network identification number of the data packet is the same as the self
network identification number, the feedback data packet is sent back; or else, the date packet is forwarded forwardly, and the data packet is eliminated after arriving at the target slave station or the working master station. When a line or the slave station fails, the backup master station can cache all data packets sent by the working master station as network positions of the backup master station and the working master station are adjacent; the feedback data packet back sent by the slave station is eliminated after arriving at the working master station and the slave station, the backup master station can receive the feedback data packet from a non-fault slave station, and thus the backup master station can receive all data packets and the feedback data packets, and hot backup of data is realized.