Biometrics authentication method and client terminal and authentication server used for biometrics authentication

摘要

In a biometrics authentication system inputting biometric information and outputting a user ID (1:N authentication system), speedup of 1:N matching on the side of a server (120) is achieved when cancelable biometrics authentication is realized in which matching (S507) is carried out while keeping biometric information concealed from the server. During registration (S407), similarity of a feature (x) to a dummy feature (D[i]) is searched and the feature (x) is transformed by using a transform parameter (R[i*]) corresponding to a nearest neighboring dummy feature (D[i*]) (transformed feature (T)). The transformed feature (T) and a group ID (i*) are transmitted to the server (120) and the server registers the transformed feature (T) at the group in a DB (122). During authentication, like the registration process, similarity search of a feature (y) is carried out and the feature (y) is transformed by using transform parameter (R[i*]) corresponding to a nearest neighboring dummy feature (D[i*]) (transformed feature (V)). The transformed feature (V) and group ID (i*) are transmitted to the server. The server (120) executes 1:1 matching between a template at the group in the DB and the transformed feature (V).