Inubushi Masanobu
Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
Chaos. 2019 Mar;29(3):033133. doi: 10.1063/1.5090177.
Random number generation is a fundamental technology behind information security. Recently, physical random number generators (RNGs), which especially harness optical chaos such as in delay-feedback lasers, have been studied intensively. Although these are promising technologies for future information security, there is little theoretical foundation. In this paper, we newly introduce a mathematical formulation of physical RNGs based on a model of chaotic dynamics and give the first rigorous results. In particular, by combining ergodic theory, information theory, and response theory of statistical physics, our theory guarantees, for the model of chaotic dynamics, the coexistence of two crucial properties necessary for physical RNGs: fast random number generation and robustness. Compared with other types of physical RNGs, our theoretical findings highlight an unnoticed advantage of chaotic dynamics utilized for physical RNGs.
随机数生成是信息安全背后的一项基础技术。近来，物理随机数发生器（RNG），尤其是利用诸如延迟反馈激光器中的光学混沌现象的随机数发生器，得到了深入研究。尽管这些是未来信息安全领域很有前景的技术，但理论基础却很薄弱。在本文中，我们基于混沌动力学模型新引入了一种物理随机数发生器的数学公式，并给出了首个严格的结果。特别地，通过结合遍历理论、信息论以及统计物理学的响应理论，我们的理论针对混沌动力学模型保证了物理随机数发生器所需的两个关键特性的共存：快速随机数生成和稳健性。与其他类型的物理随机数发生器相比，我们的理论发现突出了用于物理随机数发生器的混沌动力学一个未被注意到的优势。
