Remote authentication using vaulted fingerprint verification

This paper presents a novel approach to remotely authenticating a user by applying the Vaulted Fingerprint Verification (VFV) protocol. It proposes an adaptation of the Vaulted Verification (VV) concept with fingerprint minutia triangle representation. Over the past decade, triangle features have been used in multiple fingerprint algorithms. Triangles are constructed from three fingerprint minutiae and result in a feature vector that is translation and rotation invariant. In VFV, the user's minutia triangles are arranged into blocks; each block of triangles is paired with a chaff block. In turn, each real/chaff block is encrypted with a key that is only known to the users. These encrypted block pairs can be used to generate a "challenge" by swapping blocks according to a random bitstring and requiring the remote user to reproduce that exact string. For identity verification, the user creates a new triangle feature vector from his or her fingerprint. This feature vector is matched against each block, which allows the user to identify the "real" block in each pair and recover the bitstring. In this process, individual triangle matching rates are improved by approximate matching on the feature vectors, grouping several feature vectors together, and correcting errors on the final bitstring. This paper presents data on an optimal threshold for approximate matching, the accuracy of triangle matching, the distinguishability between a user's triangle and a chaff triangle, and the accuracy of the VFV system.