Patent ID: 11909892
Assignee: NEC CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 0:
1. An authentication system including a client, the authentication system comprising:
a second server that determines whether or not matching information matches registration information based on a concealed evaluation value of an evaluation value indicating similarity between the registration information and the matching information, the concealed evaluation value being calculated by the client;
a a first server that:
transmits a message to the client;
determines whether or not a signature is a correct signature by using a first verification key, the message, and the signature generated by the client; and
determines that authentication succeeds when the matching information matches the registration information and it is determined that the signature is the correct signature,

wherein the client
stores concealed information obtained by concealing the registration information;
calculates the concealed evaluation value based on the matching information and the concealed information; and
generates the signature based on the message by using a signature key,

wherein the second server further transmits the signature generated in the client to the first server under a condition that the matching information and the registration information are determined to match.