According to one embodiment, a device includes a memory area being used to store a first key (NKey), unique secret identification information (SecretID), and encrypted secret identification information (E-SecretID), the encrypted secret identification information (E-SecretID) being generated by encrypting the secret identification information (SecretID), the first key (NKey) and the secret identification information (SecretID) being prohibited from being read from outside, the encrypted secret identification information (E-SecretID) being readable from outside; a data generator configured to generate a session key (SKey) by using a second key (HKey), the second key (HKey) being generated based on the first key (NKey); and a one-way function processor configured to generate an authentication information by processing the secret identification information (SecretID) with the session key (SKey) in one-way function operation.