Abstract
Modern cryptographic protocols require good entropy sources. Unfortunately, many networked devices lack subsystems dedicated to this task, being potentially susceptible to random number generator (RNG) attacks. Yet, most of these systems allow software upgrades and host communication ports, providing the option of a retrofit. This work illustrates how chaotic dynamics can be used to design a sub-10$ entropy source capable of an over 48kbit/s rate and offering multiple serial communication abilities. Operation is based on a standard microcontroller and exploits a loop built around one of its analog to digital converters (ADCs). The design offers self-testing features and enables an experimental validation of some recent results on the choice of the best state quantization function to employ when using chaotic maps as RNGs.
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Notes
Considering the overhead of USB data transmission.
Similar results can be obtained with any other converter type.
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Callegari, S., Fabbri, M. & Beirami, A. Very low cost chaos-based entropy source for the retrofit or design augmentation of networked devices. Analog Integr Circ Sig Process 87, 155–167 (2016). https://doi.org/10.1007/s10470-015-0631-y
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DOI: https://doi.org/10.1007/s10470-015-0631-y