Theoretical and Practical Boundaries of Binary Secure Sketches

Julien Bringer (1) , Hervé Chabanne (1) , Gérard Cohen (2) , Bruno Kindarji (1, 2) , Gilles Zémor (3)

1 SAGEM Défense Sécurité [Massy]
2 ENST - Ecole Nationale Supérieure des Télécommunications
3 IMB - Institut de Mathématiques de Bordeaux

Fuzzy commitment schemes, introduced as a link between biometrics and cryptography, are a way to handle biometric data matching as an error-correction issue. We focus here on finding the best error-correcting code with respect to a given database of biometric data. We propose a method that models discrepancies between biometric measurements as an erasure and error channel, and we estimate its capacity. We then show that two-dimensional iterative min-sum decoding of properly chosen product codes almost reaches the capacity of this channel. This leads to practical fuzzy commitment schemes that are close to theoretical limits. We test our techniques on public iris and fingerprint databases and validate our findings.

Domaines: Théorie de l'information [cs.IT]

Julien Bringer, Hervé Chabanne, Gérard Cohen, Bruno Kindarji, Gilles Zémor. Theoretical and Practical Boundaries of Binary Secure Sketches. IEEE Transactions on Information Forensics and Security, 2008, 3 (4), pp.673--683. ⟨10.1109/TIFS.2008.2002937⟩. ⟨hal-00346970⟩