Post-Quantum Secure Two-Party Computation for Iris Biometric Template Protection

Abstract

Thinking about the protection of biometric data, future attacks using a quantum computer call for adequate resistance of biometric verification systems. Such systems are often deployed on a long-term basis and deserve strong protection due to the sensitive nature and persistence property of the data they contain. To achieve efficient template protection, we combine post-quantum secure two-party computation with secret sharing and apply the first practically implemented post-quantum secure two-party computation protocol for the purpose of biometric template protection. The proposed system ensures permanent protection of the biometric data as templates are stored and compared in the encrypted domain. For the verification, we present two options which can be achieved as real-time transactions: A well-established classical two-party computation scheme or a recent post-quantum upgrade of that scheme. Both methods maintain full biometric performance. For the database of reference templates, which is a target for attacks in a biometric system, post-quantum security is maintained throughout both verification options. Regarding the computational efficiency of our proposed system, we offer real-time computational transaction times, making our solution relevant for practical applications.