Authentication method and authentication system using biometric information and functional encryption

An authentication method using a functional encryption in an apparatus, the authentication method comprising:

• generating a master secret key and a master public key;
• generating a secret key and a public key using enrollment target personal information, the master secret key and the master public key;
• generating first information using the enrollment target personal information;
• storing the secret key and the first information in a secure area;
• generating a ciphertext encrypted using authentication target personal information and the public key;
• generating second information using the authentication target personal information;
• and
• performing authentication of the authentication target personal information using the secret key, the first information, the ciphertext and the second information,
• wherein the performing of the authentication includes:
• calculating a similarity between the enrollment target personal information and the authentication target personal information by computing an Euclidean distance of the enrollment target personal information and the authentication target personal information;
• and
• performing the authentication in relation to the similarity.

An authentication system comprising:

• an apparatus;
• and
• an authentication server including a secure area, configured to communicate with the apparatus, and further configured to perform authentication using a functional encryption,
• wherein the apparatus is configured to:
• generate a master secret key and a master public key,
• generate a secret key and a public key using enrollment target personal information, the master secret key and the master public key,
• generate first information using the enrollment target personal information,
• communicate the secret key and the first information to the authentication server,
• generate a ciphertext encrypted using authentication target personal information and the public key,
• generate second information using the authentication target personal information, and
• communicate the ciphertext and the second information to the authentication server,
• the authentication server is further configured to:
• store the secret key and the first information in the secure area,
• calculate a similarity between the enrollment target personal information and the authentication target personal information by computing an Euclidean distance of the enrollment target personal information and the authentication target personal information using the secret key, the first information, the ciphertext and the second information, without exposing the enrollment target personal information and the authentication target personal information, and
• perform the authentication in relation to the similarity, and
• the apparatus is further configured to:
• physically erase memory storing the secret key and the first information after communicating the secret key and the first information to the authentication server, and
• physically erase memory storing the ciphertext and the second information after communicating the ciphertext and the second information to the authentication server,
• wherein the authentication server is configured to physically erase memory storing the ciphertext and the second information after performing authentication.