On Quantization Schemes And Security Aspects For Biometrical Key Generation

Description

In recent years, users are starting to carry around more and more mobile devices. Many concepts for these so called wearables to form a Body Area Network have been proposed. Yet, there does not exist a ready-to-use solution for a secured connection protocol based on human biometrics and many uncertainties regarding the security of these schemes still exit. A crucial part of these systems lies in the method that generates bit sequences from accelerometer data. This master’s thesis will (1) examine the randomness of the keys generated by different gait authentication systems such as BANDANA [6], Walkie-Talkie [7] or SAPHE [2]. This resembles a quantitative approach that heavily relies on a large set of samples. Apart from that, (2) a qualitative review for possible vulnerabilities or unintentionally introduced bias affecting the generated keys will be performed. With the insights gained from this task, (3) requirements for good quantization methods will be identified and the feasability of different concepts as well as tradeoffs will be discussed. Eventually, (4) new quantization methods will be introduced and evaluated throughout the thesis. Wherever possible, (5) improvements to our approach - BANDANA - will be incorporated. (6) Guidelines for defining a proper gait authentication protocol will also be collected, if necessary. A full specification of a protocol goes beyond the scope of this thesis.