Security capacity of the fuzzy fingerprint vault

Abstract—We investigate the security of a privacy enhancing technique for fingerprint authentication known as fuzzy fingerprint vault. This technique is based on the fuzzy vault of Jules and Sudan, a scheme that allows error tolerant authentication, while pre-serving the privacy of the reference data. We explore if and under what circumstances a secure fuzzy fin-gerprint vault can be implemented. We derive both upper and lower security bounds for any attacks that attempt to recover the template from the stored reference data, and, at the same time, significantly improve the best known attack. Furthermore, we show how to select optimal parameters and evaluate both minimum minutiae match rates and minimum number of minutiae needed to obtain an appropri-ate security level. Our results quantify the security capacity of the fuzzy fingerprint vault and provide important tools for selection of suitable parameters. Keywords-biometric template protection; finger-print; fuzzy vault; polynomial reconstruction I