Abstract: A communication system (50) according to the present invention includes a first communication device (10) that functions as a main device, and a second communication device (20) that functions as a backup device for the first communication device (10). A second functional unit of the second communication device (20) transmits a response request to a first functional unit of the first communication device (10), and transmits a transfer-destination switching request to the first communication device (10) if a response to the response request has not been received from the first functional unit. If a first transfer unit receives the transfer-destination switching request from the second functional unit, the first transfer unit switches a transfer destination of packets that should be processed by the second functional unit from the first functional unit to the second functional unit.

Abstract: A communication system (50) according to the present invention includes a first communication device (10) that functions as a main device, and a second communication device (20) that functions as a backup device for the first communication device (10). A second functional unit of the second communication device (20) transmits a response request to a first functional unit of the first communication device (10), and transmits a transfer-destination switching request to the first communication device (10) if a response to the response request has not been received from the first functional unit. If a first transfer unit receives the transfer-destination switching request from the second functional unit, the first transfer unit switches a transfer destination of packets that should be processed by the second functional unit from the first functional unit to the second functional unit.

Abstract: Provided is a transmitting and receiving system and method in which a transmitting and receiving device mounted on an operation system unit can process a signal received from an equipment connected to a standby system unit and a signal to be transmitted to the equipment connected to the standby system unit. A data signal and a control signal to be transmitted to a receiving device of the operation system unit are multiplexed by a parallel/serial conversion using a multiplexer. The signals are transmitted to the operation system unit as a serial received signal. The signal is demultiplexed by a serial/parallel conversion using a demultiplexer of the operation system unit. Further, a data signal and a control signal to be transmitted to the equipment connected to the standby system unit are multiplexed by a parallel/serial conversion using a multiplexer. The signals are transmitted from the operation system unit to the standby system unit as a serial signal to be transmitted.

Abstract: Provided is a transmitting and receiving system and method in which a transmitting and receiving device mounted on an operation system unit can process a signal received from an equipment connected to a standby system unit and a signal to be transmitted to the equipment connected to the standby system unit. A data signal and a control signal to be transmitted to a receiving device of the operation system unit are multiplexed by a parallel/serial conversion using a multiplexer. The signals are transmitted to the operation system unit as a serial received signal. The signal is demultiplexed by a serial/parallel conversion using a demultiplexer of the operation system unit. Further, a data signal and a control signal to be transmitted to the equipment connected to the standby system unit are multiplexed by a parallel/serial conversion using a multiplexer. The signals are transmitted from the operation system unit to the standby system unit as a serial signal to be transmitted.