Patent ID: 8466775

Claim:
A method for authenticating an electronic tag comprising: receiving, by the electronic tag, a request packet for access authentication from a reader, wherein the request packet carries a first parameter selected by the reader; sending, by the electronic tag, a response packet for access authentication to the reader, wherein the response packet for access authentication comprises the first parameter and a second parameter selected by the electronic tag; receiving, by the electronic tag, an acknowledgement packet for access authentication fed back from the reader, wherein the acknowledgement packet for access authentication is constructed after the reader receives the response packet for access authentication and after the electronic tag passes the authentication from the reader; acknowledging, by the electronic tag, the acknowledgement packet for access authentication; wherein the response packet for access authentication further comprises: a temporary identity of the electronic tag, which has a value of H(ID∥N1); a value for message integrity check calculated by the electronic tag, which equals to H(TempID∥N2∥Key); and wherein the acknowledgement packet for access authentication comprises: the second parameter selected by the electronic tag; and a value for message integrity check calculated by the reader, which equals to H(N2∥Key).