Gbits/s physical-layer stream ciphers based on chaotic light

In this paper, we propose a novel high-speed stream cipher encryption scheme based on the true random key generated by a chaotic semiconductor laser. A 5-Gbits/s non-return-to-zero plaintext is successfully encrypted and decrypted using this cryptography by numerical simulations. Compared with chaos-based optical communications for a single channel utilizing analog chaotic optical carrier, the performance of the proposed setup of stream ciphers based on true random numbers generated by chaotic light is improved. The scheme overcomes the shortcoming of quality decrease of chaos communications caused by decline of chaos synchronization. The proposed setup can be applied in the areas of real-time high-speed physical encryption.