Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast e...Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.展开更多
A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The ch...A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The chaotic sequence generated by Chua’s circuit model realizes two-level encryption of displacement masking and constellation rotation for3 D constellations.We successfully conduct an experiment demonstrating 8.7 Gb/s 3 D-CAP-8 data transmission over25 km standard single-mode fiber.With two-level constellation masking,a key space size of 2.1×1085 is achieved to bring about high security and good encryption performance,suggesting broad application prospects in future short-range secure communications.展开更多
Among physical layer encryption schemes,the quantum noise stream cipher(QNSC)has garnered significant attention due to its compatibility with high-speed commercial fiber-optic communication systems.After careful analy...Among physical layer encryption schemes,the quantum noise stream cipher(QNSC)has garnered significant attention due to its compatibility with high-speed commercial fiber-optic communication systems.After careful analysis of the encryption scheme,we reveal that QNSC transmission systems exhibit a security vulnerability in their encoding scheme.This vulnerability limits quantum noise to alerting high-order information bits in plaintext-dependent regions,creating structured ciphertext concealment.Numerical simulation and experimental verification both indicate that an eavesdropper can use quantization-attack to crack this vulnerability.Existing security assessment methods will overestimate the system's security under quantization-attack.In addition,system security demonstrates a strong linear dependence on the plaintext modulation format,rather than the ciphertext modulation format as is widely presumed.To further enhance system security,the probability distribution is further introduced into the encoding process of ciphertext.The experiment results show that we not only achieved random concealment of ciphertext by quantum noise but also enhanced the eavesdropper's symbol error rate by~86%and maximally expanded the key space of the QAM-QNSC system by 2^(27.2).展开更多
基金supported in part by the National Natural Science Foundation of China Project under Grant 62075147the Suzhou Industry Technological Innovation Projects under Grant SYG202348.
文摘Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.
基金the National Key Research and Development Program of China(No.2018YFB1801302)National Natural Science Foundation of China(Nos.61835005,61822507,61522501,61475024,61675004,61705107,61727817,61775098,61720106015,and 61875248)+2 种基金Beijing Young Talent(No.2016000026833ZK15)Open Fund of IPOC(BUPT)(No.IPOC2019A011)Jiangsu Talent of Innovation and Entrepreneurship,Jiangsu Team of Innovation and Entrepreneurship,and Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX200963)。
文摘A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The chaotic sequence generated by Chua’s circuit model realizes two-level encryption of displacement masking and constellation rotation for3 D constellations.We successfully conduct an experiment demonstrating 8.7 Gb/s 3 D-CAP-8 data transmission over25 km standard single-mode fiber.With two-level constellation masking,a key space size of 2.1×1085 is achieved to bring about high security and good encryption performance,suggesting broad application prospects in future short-range secure communications.
基金National Natural Science Foundation of China(62431024,62575248,U22A2089)Key Technology Research and Development Program of Shandong Province(2023CXPT100)Outstanding Young Scientist Fund of Sichuan Provincial Natural Science Foundation(2025NSFJQ0052)。
文摘Among physical layer encryption schemes,the quantum noise stream cipher(QNSC)has garnered significant attention due to its compatibility with high-speed commercial fiber-optic communication systems.After careful analysis of the encryption scheme,we reveal that QNSC transmission systems exhibit a security vulnerability in their encoding scheme.This vulnerability limits quantum noise to alerting high-order information bits in plaintext-dependent regions,creating structured ciphertext concealment.Numerical simulation and experimental verification both indicate that an eavesdropper can use quantization-attack to crack this vulnerability.Existing security assessment methods will overestimate the system's security under quantization-attack.In addition,system security demonstrates a strong linear dependence on the plaintext modulation format,rather than the ciphertext modulation format as is widely presumed.To further enhance system security,the probability distribution is further introduced into the encoding process of ciphertext.The experiment results show that we not only achieved random concealment of ciphertext by quantum noise but also enhanced the eavesdropper's symbol error rate by~86%and maximally expanded the key space of the QAM-QNSC system by 2^(27.2).
