Error Analysis of Identification Information Calculated From Fingerprints

Péter ORVOS

Endre SELÉNYI, Zoltán HORNÁK

For the verification of digital signatures it is indispensable that the signing person must be unambiguously identified. Cryptography solves this problem by identifying the signing key, however it is only assumed that just its legal owner possesses the secret key, hence current implementations cannot prove that the owner used the appropriate key being based on only property and optionally knowledge based user identification.

My work aims to enforce this correspondence by integrating the owner's biometric identification into the key preparation process extracting information from the owner's fingerprint, without what the secret key that is stored encoded cannot be prepared for signing. This way the key can only be restored for generating the digital signature if the owner is identified successfully.

For this reason some kind of information should be extracted from the fingerprint image. This information may also be used for other purposes as well (e.g. biometric file encryption or as personal ID).

On the other hand biometric identification methods rather aim the comparison of biometric samples than the calculation of any kind of personal identification information from them that further could be used for secret key encryption. Therefore the proposed algorithm will both suffer from the decision errors of the biometric identification method itself and the problems introduced by the approach of extracting information.

The article and the lecture aim the introduction of the possible sources of decision errors using a multilevel approach, in which each level can be evaluated separately, finally resulting cumulative error rates. This error model also provides the ability to compare the possibilities of successful information extraction to the acceptation of the actual sample in a conventional biometric authentication system.