Patent ID: 7673008

Claim:
A network system comprising: a plurality of devices connected to a network, each of the devices is assigned an ordinal rank in the system in which one of the devices with highest ordinal rank functions as a master device and other devices of the devices with other ordinal ranks function as general devices, wherein each of the other devices includes: a master device checking unit configured to operate when one of the other devices is functioning as one of the general devices check whether the one of the devices functioning as the master device exists in the system; a control unit configured to control the one of the other devices to function as the master device when an ordinal rank of the one of the other devices is judged to be highest in the system; and a priority reassigning unit configured to reassign the other ordinal ranks of the each of the other devices connected to the network when the one of the other devices has a higher ordinal rank than the master device in the system, wherein the reassigning the other ordinal ranks further includes updating the ordinal rank of the each of the devices connected to the network based on a corresponding master aptitude value.