Patent ID: 8378790

Claim:
A method for locking a tag device, the method performed by a mobile processor and comprising: transmitting, to a reading device, a reading command, the reading command instructing the reading device to inform a unique identifier of the tag device, the unique identifier identifying the tag device uniquely and the unique identifier having a variable length, wherein the reading device performs a reading operation in response to the reading command, wherein a reading response is generated according to a result of the reading operation, wherein, when the reading operation is successfully performed, the reading response includes a total length field, a first payload field, and a second payload field, wherein the total length field specifies a total length of the first payload field and the second payload field, the first payload field having a fixed length, and the second payload field having a variable length, wherein the first payload field comprises a protocol control (PC) section, and wherein the unique identifier is inserted into the second payload field; receiving, from the reading device, the reading response including the unique identifier and the PC section; obtaining a unique identifier length by subtracting the fixed length from the total length, the unique identifier length specifying a length of the unique identifier; and transmitting, to the reading device, a locking command for controlling a lock function for preventing a change or an erase of content included in the tag device, wherein the locking command comprises the unique identifier, the unique identifier length, an access password, and lock data for controlling the lock function, wherein the reading device detects the tag device to be locked with the received unique identifier, wherein the reading device accesses the detected tag device with the received access password, and wherein the reading device locks the accessed tag device in order to prevent a change of content included in the tag device.