Patent ID: 8416057

Claim:
A method for identifying an authentication status of a first item through use of an algorithm configured to be executed within a first Radio Frequency Identifier (RFID) tag associated with the first item and configured to be executed within a second RFID tag associated with a second item that is a genuine representation of the first item, wherein the algorithm performs: receiving a first parameter as a first input and a second parameter as a second input; forming a concatenation (C) of a parameter value, the second parameter, and a key value; computing a hash (H) by applying a hashing function to the concatenation C; and returning an identifier (Id) as a first output and the hash H as a second output, wherein the algorithm determines the parameter value to be the identifier Id if the first parameter is zero or to be the first parameter if the first parameter is not zero, wherein the method is performed by an apparatus comprising an RFID reader and a computer coupled to the RFID reader, and wherein the method comprises: said RFID reader transmitting zero (0) and a random number R from the RFID reader to the first RFID tag; after said transmitting zero and the random number R, said RFID reader receiving from the first RFID tag first data comprising an identifier Id 1 and a hash H 1 , said identifier Id 1 being an identifier of the first RFID tag as the identifier Id, said hash H 1 consisting of the hash H computed by the algorithm as a result of the algorithm being executed in the first RFID tag; after said receiving the first data, said computer determining that the identifier Id 1 in the first data is equal to an RFID identifier of the first item stored in a database; after determining that the identifier Id 1 in the first data is equal to the RFID identifier, said RFID reader transmitting the identifier Id 1 and the random number R to the second RFID tag; after said transmitting the identifier Id 1 and the random number R, said RFID reader receiving from the second RFID tag second data comprising an identifier Id 2 and a hash H 2 , said identifier Id 2 being an identifier of the second RFID tag stored in the second RFID tag as the identifier Id, said hash H 2 consisting of the hash H computed by the algorithm as a result of the algorithm being executed in the second RFID tag; after said receiving the second data, said computer determining the authentication status of the first item by ascertaining whether H 1 is equal to H 2 and subsequently determining that the authentication status is that the first item is authentic or counterfeit if said ascertaining has ascertained that H 1 is equal to H 2 or that H 1 is unequal to H 2 , respectively; said computer communicating the authentication status to a user.