Integrating key generation and distribution with the quantum noise stream cipher system without compromising the transmission performance

Abstract

We propose and experimentally demonstrate a secure quantum noise stream cipher transmission system that integrates key generation and distribution. At the stage of carrier phase recovery, the estimated phase noise is used to generate randomness keys without additional equipment. Based on direct sequence spread spectrum technology, we integrate the distributed keys with quantum noise stream cipher signals. The key distribution and encryption transmission can be completed simultaneously without occupying additional bandwidth or time slots. By changing the position of distributed keys in the encryption base, the BER performance of QAM/QNSC signals cannot be affected by the keys. Experimental results demonstrate that the 54.5 Mbps key distribution and 31 Gbps encryption transmission without OSNR penalty can be achieved simultaneously over a 120 km standard single-mode fiber.

Time-Division Multiplexed Optical Covert Communication System Based on Gain-Switched Optical Pulses

“…Photonic-layer secure communication safeguards against adversarial detection in the optical domain by employing a range of security technologies, including optical chaos [1][2][3][4][5], optical code division multiplexing [6][7][8], quantum noise randomized ciphers [9][10][11][12], optical frequency hopping [13][14][15], quantum key distribution [16,17], and optical covert communication (OCC) [18][19][20][21][22][23]. OCC requires a higher level of security than merely protecting the content from unauthorized access through encryption, and the security requirement is imperceptibility for optical covert communication.…”