Tapping Eavesdropper Designs Against Physical Layer Secret Key in Point-to-Point Fiber Communications

With the growing demand for service access and data transmission, security issues in optical fiber systems have become increasingly important subject of increased research. Physical layer secret key generation (PL-SKG), which leverages random but common channel properties at legitimate parties, has been shown to be a secure, low-cost, easily deployed technique as opposed computational-based cryptography, quantum, chaos methods that rely on precise equipment. However, eavesdropper (Eve) potential current PL-SKG communications overlooked by most studies date. Unlike wireless communications, where randomness comes from spatial multi-paths cannot all captured Eves, (from transmitted pilots or randomness) is contained signals inside fiber. This, therefore, enables tapping Eve reconstruct features users its received signals, further decrypt featured-based keys. To implement this idea, we designed two schemes against polarization mode distortion (PMD) based two-way cross multiplication PL-SKG. The simulation results show our proposed Eves can successfully feature relied upon, leading rate (SKR) reductions between three four orders magnitude studied. As result, reveal demonstrate novel eavesdropping provide challenges physical designs. We hope more insightful vision critical evaluation design new links, comprehensively intelligent networks.