Patent ID: 7689479

Claim:
A method for protecting product information about one or more selected products attached to one of a plurality of tags, comprising the steps of: receiving the product information for identifying the product stored in one of the plurality of tags attached to one or more selected products; generating a local identifier in accordance with a predetermined rule according to the reception of the product information; creating a lock for the product information stored in the one of the plurality of tags; sending the product information corresponding to the local identifier, in order to store the product information in a product information recording medium isolated from the one of the plurality of tags; generating a receipt identifier for identifying the product information recording medium; encrypting the receipt identifier without compression of the receipt identifier, with the encryption of the receipt identifier specific to the product information recording medium; generating the passcode for the one of the plurality of tags based on the encryption of the receipt identifier; storing the passcode on the product information recording medium; sending the local identifier to the one of the plurality of tags, in order to replace the product information with the corresponding local identifier, wherein the local identifier is a sequential number; assigning each of a plurality of pieces of the product information a separate instance of the sequential number; generating a replacement lock for the product information stored in the one of the plurality of tags after replacing the product information with the sequential number; generating a replacement passcode for the one of the plurality of tags based on the receipt identifier; determining whether there is product information to be restored by comparing a first received passcode to a second passcode stored in the product information recording medium; restoring the product information to the one of the plurality of tags in place of the sequential number; applying a write protection lock to the one of the plurality of tags after the product information is restored; controlling repetition of the sequential number with a repetition controller, wherein the sequential number is unique within the product information but not unique to a product; and determining whether the number of selected products is greater than the sequential number.