32 Gb/s physical-layer secure optical communication over 200 km based on temporal dispersion and self-feedback phase encryption
Zhensen Gao, Qihua Li, Lihong Zhang, Bin Tang, Ying Luo, Xulin Gao, Songnian Fu, Zhaohui Li, Yuncai Wang, Yuwen Qin
Abstract
Providing physical layer security at the lowest network layer in fiber-optic communication systems is a technical challenge worldwide. Here, we propose and experimentally demonstrate a pure hardware optical encryption scheme based on temporal spreading and self-feedback phase encryption for high-speed and long-distance physical-layer secure optical communication. A record high bit-rate-distance product of 6400 Gb/s km is successfully achieved by the secure transmission of a 32 Gb/s on-off-keying modulated confidential signal over a 200 km optical fiber link. The demonstrated scheme is fully compatible with conventional optical transmission systems and can be operated in a pluggable manner, which may pave a new path to ultra-high-speed physical-layer secure optical communication in the future.