Patent ID: 6934291

Claim:
An ATM network system comprising: a network device; and a plurality of user devices, wherein said network device receives from one of said plurality of user devices a first specific ATM cell which has a specific VPI value and a specific VCI value in its header and is loaded in an information field with a device ID for identifying said one of said plurality of user devices and transmits, to said one of said plurality of user devices, a second specific ATM cell which has the specific VPI value and the specific VCI value in its header and is loaded with the device ID and a proper VPI value on an information field, and said one of said plurality of user devices acquires the device ID from the network device on first connection, transmits the first specific ATM cell after the first connection with said network device, receives the second specific ATM cell, and holds the proper VPI value as its own VPI value when the device ID loaded in the second specific ATM cell is confirmed to be the acquired device ID.