An authentication system, comprising:
- an authentication server comprising a memory that stores authentication information to be used for authentication and a processor coupled to the memory of the authentication server;
- a plurality of sub-authentication server comprising a memory and a processor coupled to the memory of the sub-authentication server;
- a terminal comprising a memory and a processor coupled to the memory of the terminal, and
- a management terminal comprising a memory and a processor coupled to the memory, wherein
- the processor of the authentication server executes a process comprising
- verifying, when receiving an authentication request which is to request to authenticate biometric information of a user using the terminal, the authentication information to authenticate the transmission origin of the authentication request using the authentication information for each sub-authentication server, when receiving the authentication request,
- selecting the sub-authentication server where a degree of similarity calculated as a verification result becomes a predetermined threshold value or less, and
- transmitting authentication information used to authenticate a transmission origin of the authentication request, to selected one of the plurality of sub-authentication server,
- the processor of the authentication server and/or the processor of the sub-authentication server executes a process comprising transmitting identification information to identify the sub-authentication server to which the authentication information is transmitted by the authentication server, to the terminal that transmits the authentication request,
- the memory of the terminal
- stores identification information to identify a transmission destination of the authentication request;
- the processor of the terminal executes a process comprising
- transmitting the authentication request to a transmission destination identified with the identification information stored by the memory of the terminal;
- and
- updating the identification information stored in the memory of the terminal using the identification information, when receiving the identification information, and
- the memory of the sub-authentication server
- stores the authentication information transmitted from the authentication server to the sub-authentication server,
- the processor of the sub-authentication server executes a process comprising authenticating the transmission origin of the authentication request using the authentication information stored in the memory of the sub-authentication server, when receiving the authentication request, and
- the processor of the authentication server and/or the management terminal further executes a process comprising
- deleting a part of the authentication information stored by the memory of the sub-authentication server with respect to the sub-authentication server where the frequency of performing the authentication is high as compared with the other sub-authentication servers,
- storing the authentication information deleted in the memory of the sub-authentication server;
- with respect to the sub-authentication server where the frequency of performing the authentication is low as compared with the other sub-authentication servers, and
- transmitting identification information to identify the sub-authentication server becoming the storage destination where the authentication information is stored, to the transmission origin authenticated using the authentication information deleted.