A packing material, a tag, a certificate, paper money, and securities, each of which can be surely prevented from counterfeiting or deception. A plurality of wireless tags used for an object such as a packing material, a tag, a certificate, paper money, or securities. The location of the plurality of wireless tags attached to each object is varied on the object such that the object can be identified. Then, the object using the wireless tags is identified by detecting the location of the plurality of wireless tags attached to each object. The more random the locations of the wireless tags, the more certain it becomes to identify the object and to prevent or detect the counterfeiting of the object or deception.