Patent ID: 9544138
Date: 2017-01-10
CPC Classifications: H04L

Claim:
1. An authentication method between an authenticatee device having a first memory which stores key information having a data structure composed of encrypted slot key sequences, secret information of a matrix form, and encrypted secret information which is created by encrypting the secret information, and an authenticator device having a second memory which authenticates the authenticatee device, comprising: receiving, by the authenticator device, the encrypted secret information and the key information; selecting an encrypted slot key sequence corresponding to a device index stored in the second memory of the authenticator device from the encrypted slot key sequences in the key information received from the authenticatee device, the device index corresponding to the authenticator device; decrypting the encrypted slot key sequence by a device key stored in the second memory, to produce a sequence of a slot index and a slot key; selecting, by the authenticator device, an element corresponding to the slot index from the encrypted secret information; executing, by the authenticator device, a decryption process on the element of the encrypted secret information by using the slot key to produce an element of the secret information; using a compression arithmetic circuit in the authenticatee device to perform an arithmetic operation on the element and produce an authentication value; and authenticating the authenticatee device using the authentication value.