Patent ID: 8473774

Claim:
A networking system, comprising: a plurality of main devices, one of the main devices acting as an original master main device, and remaining main devices acting as slave main devices, wherein the original master main device manages all hardware resources installed in the plurality of main devices on a network and exerts all call controls on the network, wherein the system selectively performs one of a first changeover operation and a second changeover operation; in the first changeover operation, each of the slave main devices always monitors a communication connection to the master main device, and determines that the original master main device malfunctions, when the communication connection with the master main device cannot be held for a predetermined time, and then one of the slave main devices, having a highest priority, substitutes for the original master main device to act as a new master main device; and in the second changeover operation, a main device specified by an ID is forcedly set to act as the master main device, and wherein when the slave main device having acted as the original master main device recognizes connection from a terminal that is set to communicate with the original master main device according to a preset IP address, the slave main device redirects the connection from the terminal to the new master main device by transferring data from the terminal to the new master main device, and relaying data from the new master main device to the terminal.