Security and Efficiency of Biometric Template Protection for Identification

The Biometric Template Protection (BTP) Technology includes Cancelable Biometrics(CB), Biometric Cryptosystem (BC), and Biometric Signature (BS). CB schemes cannot satisfy security requirements on irreversibility and spoofing difficulty if enrolled data leak from multiple entities. On the other hand, it is considered that well-implemented BC schemes such as fuzzy extractor or BS schemes such as fuzzy signature satisfy the security requirements. However, when these schemes are naively applied to identification, computation and communication cost increases. In this paper, we define efficiency requirements based on computation and communication cost for Biometric Template Protection for Identification (BTPI). Then, we show that BTPI schemes based on conventional BTP schemes cannot satisfy requirements on security and efficiency simultaneously. Next, we propose a novel BTPI scheme obtained by combining fast CB and secure BC or BS. The proposed scheme achieves both requirements under certain assumptions on the publicity of biometric features used for the proposed scheme.