With the rapid increase of smart devices in the Internet of Things, more and more visible light (VL) systems, e.g., VL communication (VLC) and VL sensing (VLS), are developed on the existing light fixtures to offload the current crowded spectrum, how to guarantee the authenticity of the VL signal in these systems becomes an urgent problem. This is because almost all of today’s light fixtures are unprotected and can be openly accessed by almost anyone and, hence, are susceptible to spoofing attacks. As such, ensuring received VL signals are coming from the authentic transmitters (LEDs), rather than from a spoofer, is the key in ensuring the quality and correctness of the VL communication and sensing outcomes. Existing authentication methods are either not directly applicable to signal-level authentication, or have poor scalability. In this article, by exploiting the intrinsic linear superposition characteristics of VL, we propose VL-Watchdog, a scalable and always-on signal-level spoofing detection framework that is applicable to both VLC and VLS systems. VL-Watchdog is based on redundant orthogonal coding of the transmitted VL, and can be implemented as a small hardware add-on to an existing VL system. A proof-of-concept testbed was developed to verify the feasibility of VL-Watchdog. The effectiveness of the proposed framework was validated through extensive numerical evaluations against a comprehensive set of factors.

中文翻译：

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VL-Watchdog：使用冗余正交编码的可见光欺骗检测

随着物联网中智能设备的快速增加，越来越多的可见光（VL）系统，例如VL通信（VLC）和VL传感（VLS），被开发在现有的灯具上，以卸载当前拥挤的光谱，如何保证这些系统中VL信号的真实性成为一个亟待解决的问题。这是因为当今几乎所有的灯具都没有受到保护，几乎任何人都可以公开访问，因此容易受到欺骗攻击。因此，确保接收到的 VL 信号来自真实的发射器 (LED)，而不是来自欺骗器，是确保 VL 通信和传感结果的质量和正确性的关键。现有的认证方法要么不能直接应用于信号级认证，要么扩展性差。在本文中，通过利用 VL 固有的线性叠加特性，我们提出了 VL-Watchdog，这是一种可扩展且始终在线的信号级欺骗检测框架，适用于 VLC 和 VLS 系统。VL-Watchdog 基于传输的 VL 的冗余正交编码，可以作为现有 VL 系统的小型硬件插件来实现。开发了一个概念验证测试平台来验证 VL-Watchdog 的可行性。通过针对一系列综合因素的广泛数值评估，验证了所提出框架的有效性。VL-Watchdog 基于传输的 VL 的冗余正交编码，可以作为现有 VL 系统的小型硬件插件来实现。开发了一个概念验证测试平台来验证 VL-Watchdog 的可行性。通过针对一系列综合因素的广泛数值评估，验证了所提出框架的有效性。VL-Watchdog 基于传输的 VL 的冗余正交编码，可以作为现有 VL 系统的小型硬件插件来实现。开发了一个概念验证测试平台来验证 VL-Watchdog 的可行性。通过针对一系列综合因素的广泛数值评估，验证了所提出框架的有效性。