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arXiv · 2103.00790

Physical Watermarking for Replay Attack Detection in Continuous-time Systems

Bahram Yaghooti·Raffaele Romagnoli·Bruno Sinopoli
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Abstract

Physical watermarking is a well established technique for replay attack detection in cyber-physical systems (CPSs). Most of the watermarking methods proposed in the literature are designed for discrete-time systems. In general, real physical systems evolve in continuous time. In this paper, we analyze the effect of watermarking on sampled-data continuous-time systems controlled via a Zero-Order Hold. We investigate the effect of sampling on detection performance and we provide a procedure to find a suitable sampling period that ensures detectability and acceptable control performance. Simulations on a quadrotor system are used to illustrate the effectiveness of the theoretical results.

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Bahram Yaghooti, Raffaele Romagnoli, Bruno Sinopoli. 2021-03-01. Physical Watermarking for Replay Attack Detection in Continuous-time Systems. https://arxiv.org/abs/2103.00790

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