Hyper-Chaotic Systems for Physical Layer Security in Next-Generation Optical and Wireless Networks : A Review

As optical communication networks evolve to support massive data rates, securing the physical layer against advanced cryptanalytic threats has become a paramount challenge. Hyper-chaotic laser systems have emerged as a robust solution, providing high-dimensional, deterministic randomness that outperforms conventional low-dimensional chaos. This study provides a comprehensive technical review of the rapid advancements in chaotic optical communication systems from 2020 to 2026. By analyzing twenty-two seminal research papers, the study highlights the strategic transition from low-dimensional chaos to hyper-chaotic systems to fortify physical layer security against evolving cryptanalytic threats. The analysis focuses on advanced generation mechanisms, such as dynamically variable-delay feedback, cascaded optical feedback, and self-phase modulated injection, emphasizing their efficacy in suppressing the time-delay signature. Furthermore, the paper evaluates modern synchronization methodologies, including AI-driven and adaptive synchronization, assessing their robustness in terms of parameter tolerance and correlation coefficient stability. Aggregated data reveals a significant leap in transmission performance, with bit rates exceeding 112 Gbps and correlation coefficients reaching over 0.95 in optimized architectures. These developments have successfully minimized the Bit Error Rate to levels that ensure high reliability in both fiber-optic and wireless troposcatter channels. This review identifies critical trade-offs between system complexity and security, providing a roadmap for future research in high-speed secure optical networks.