Leveraging Reliable Bits: ECC Design Consideration For Practical Secure Biometric Systems

It is well-known that a biometric fuzzy vault can be constructed by applying an error correcting code (ECC) to a biometric signal. This is attractive because authentication only requires the check bits of the ECC to be stored on the access control device, whereas the personal biometric traits need not be stored. For a given coding rate, the ECC attempts to correct the errors between an enrollment biometric and the provided probe, and authenticates if it is successful in doing so. Unfortunately, most implementations of biometric fuzzy vaults have very poor robustness to the inherent noisiness of biometric measurements. In this paper, we provide ECC design considerations for secure biometric systems, which provide both better robustness and greater security. In particular, for any feature extraction algorithm, we propose to reorder the feature bits according to their reliability, and associate the reliable bits with high-degree variable nodes in the graph of the ECC. Further, the reliability of a bit is measured at enrollment and used to initialize the ECC decoding. Experiments on an extensive database show considerable reduction in the false reject rate, while restricting the successful attack rate to a very low value. IEEE Workshop on Information Forensics and Security This work may not be copied or reproduced in whole or in part for any commercial purpose. Permission to copy in whole or in part without payment of fee is granted for nonprofit educational and research purposes provided that all such whole or partial copies include the following: a notice that such copying is by permission of Mitsubishi Electric Research Laboratories, Inc.; an acknowledgment of the authors and individual contributions to the work; and all applicable portions of the copyright notice. Copying, reproduction, or republishing for any other purpose shall require a license with payment of fee to Mitsubishi Electric Research Laboratories, Inc. All rights reserved. Copyright c ©Mitsubishi Electric Research Laboratories, Inc., 2009 201 Broadway, Cambridge, Massachusetts 02139