Patent ID: 8732466

Claim:
A host device which can execute an authentication process with a memory device provided with a first area where read is restricted and readable second area and third area, wherein the host device has first key data recorded as a set and is configured to: read encrypted secret data stored in the second area; decrypt the encrypted secret data with family key data obtained based on family key block data read from the third area; read key index data stored in the second area and select, from the set, the first key data corresponding to the key index data; generate session key data by executing an AES (Advanced Encryption Standard) encryption process with number data and the selected first key data; execute a conversion process using a one-way function with, as input values, the session key data and secret data generated by decrypting the encrypted secret data to thereby generate verification data; and execute a conversion process using a one-way function with the secret data as an input value to thereby generate EMID.