Un séminaire de l’équipe Armedia est organisé par Dijana Petrovska le mercredi 29 mai 2019 à 14h avec un intervenant de Leuven. Sur le site d’Evry la salle H218 a été réservée, sur Saclay, la salle de visio de NanoInnov.

Presenté par: Enrique Aragones Rua (from IMEC-COSIC KU Leuven https://www.esat.kuleuven.be/cosic/

Title: « Cryptographic Key Derivation from Continuous Sources »

Abstract:
The procedure for extracting a cryptographic key from noisy sources, such as biometrics and Physically Uncloneable Functions (PUFs), is known as Fuzzy Extractor (FE). Although FE constructions deal with discrete sources, most noisy sources are continuous. In the continuous case, it is required to transform the source to a discrete one. In this talk I will present a (i) model-based uncoupling construction that deals directly with the continuous noisy source and produces helper data uncoupling the discrete representation from the noisy source, guaranteeing the diversity of the discrete representation, and making it more robust; and a (ii) strengthened uncoupled fuzzy extractor, suitable for privacy-preserving applications, that integrates an additional fixed authentication factor and obtains a key uncoupled to the noisy sources and unlinkable helper data. As a working example, I will introduce optimal model-based uncoupling constructions for Gaussian sources. Specifically, I will depict the optimal procedures to extract (i) one or multiple bits from single Gaussian source, (ii) one bit from several unreliable Gaussian sources; and a general procedure to obtain an optimal uncoupled FE from Gaussian source(s). Some experimental results will show that the proposed constructions achieve much higher security levels for wide operational scenarios, approximately doubling the obtained effective key lengths without affecting false rejection rates.

Biography:

I studied Telecommunications Engineering in the University of Vigo (Spain). My Master Thesis was “Diseño y evaluación de un sistema de comunicaciones sobre líneas de baja potencia basado en OFDM”, which would be in English “Design and evaluation of a communication system on low power lines based on OFDM”. I obtained my PhD in Telecommunications Engineering from the University of Vigo, on May 14th 2008. My dissertation title was: “Robust audiovisual techniques for person authentication”. Since then, I have been working in different fields, always related to the use, implementation and protection of biometric systems. I have been working in Gradiant (Galician Technoloogy Center for Telecommunications) in different projects related to the development and deployment of biometric technologies. My research activities have been focused on the biometrics field, first for the development of new (and more accurate) biometric systems, and then, following the natural trend in this topic, trying to solve the inherent problems that affect the deployment and secure use of this kind of systems. I started in COSIC on September 2015, and I my research activities are now totally focused on the enhancement of privacy and security in biometric authentication systems, and on the use of these privacy and security enhancing technologies in similar technology fields.