LightGuard: Transparent WiFi Security via Physical-Layer LiFi Key Bootstrapping

Computer Science > Cryptography and Security [Submitted on 1 Apr 2026] LightGuard: Transparent WiFi Security via Physical-Layer LiFi Key Bootstrapping Shiqi Xu, Yuyang Du, Mingyue Zhang, Hongwei Cui, Soung Chang Liew WiFi is inherently vulnerable to eavesdropping because RF signals may penetrate many physical boundaries, such as walls and floors. LiFi, by contrast, is an optical method confined to line-of-sight and blocked by opaque surfaces. We present LightGuard, a dual-link architecture built on this insight: cryptographic key establishment can be offloaded from WiFi to a physically confined LiFi channel to mitigate the risk of key exposure over RF. LightGuard derives session keys over a LiFi link and installs them on the WiFi interface, ensuring cryptographic material never traverses the open RF medium. A prototype with off-the-shelf WiFi NICs and our LiFi transceiver frontend validates the design. Subjects: Cryptography and Security (cs.CR); Hardware Architecture (cs.AR); Networking and Internet Architecture (cs.NI) Cite as: arXiv:2604.01092 [cs.CR]   (or arXiv:2604.01092v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2604.01092 Focus to learn more Submission history From: Shiqi Xu [view email] [v1] Wed, 1 Apr 2026 16:19:12 UTC (6,689 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-04 Change to browse by: cs cs.AR cs.NI References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)