Biometric key-binding using lattice masking^†

In biometrics, template protection technology aims to protect the confidentiality of a biometric template (i.e., enrolled biometric information) by certain conversion. Here, we focus on the key-binding approach for template protection. This approach generates a secure template from joint data of a user's specific key with a user's template, and the key can be correctly extracted from the secure template only when a queried biometric feature is close to the plain template. While almost all conventional schemes use the error correcting code technique, we present a new technique based on lattices to give a new key-binding scheme. Our proposed scheme can provide several requirements (e.g., diversity and revocability) for template protection, which cannot be provided by error correcting code based typical schemes such as the fuzzy commitment and the fuzzy vault.