Patent ID: 7715325

Claim:
A network system, comprising: at least one new device newly connected to a master device through a network, for transmitting a plugged-in request message containing an initial address through the network, receiving an address change request message containing a logical address, and changing the initial address to the logical address; and at least one master device connected to the new device through the network, for receiving the plugged-in request message from the new device, setting the logical address for the new device, and transmitting the address change request message containing the logical address to the new device; wherein when the master device receives a plurality of plugged-in request messages within a predetermined time, the master device decides whether the plugged-in request messages are inputted from the same kind of product devices before setting the logical address, transmits join request messages containing temporary logical address ranges to the same kind of new devices when there are the messages inputted from the same kind of product devices, or transmits the join request messages containing the temporary logical address ranges respectively to the new product devices when there is no message inputted from same kind of product devices, wherein the new device sets an arbitrary value as a temporary logical address within the temporary logical address range, changes the logical address to the temporary logical address, and transmits a join ACK response message containing the temporary logical address to the master device, wherein the master device decides whether the temporary logical addresses contained in the join ACK response messages are identical, re-transmits join request messages containing new temporary logical address ranges to the new devices transmitting the same temporary logical addresses, and transmits address change request messages containing new logical addresses to the other new devices, wherein the initial address comprises at least a product code and a logical address of the new device, and the new device changes the logical address to the logical address set by the master device.