Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

IEEE International Conference on Telecommunications and Photonics (ICTP)

Discrete Modulated Continuous-Variable Quantum Key Distribution: Security and Noise Tolerance Enhanced by Decoy States and Effective Error Correction Protocol Integration

Abdul Mukit, Md Sabbir Hossen Bijoy, Sajid Muhaimin Choudhury, Md Tareq Mahmud

Published Dec 21, 2023• 0 citations
Publisher

Abstract

As the possibility of a genuine, functioning quantum computer becomes closer to reality every day, so does the urge to use the principles of quantum physics to improve the security of communications. One of the most studied areas of quantum communication is quantum key distribution (QKD), however there are still challenges to overcome, such as low detection accuracy, the need for extensive computation, and the lack of extremely efficient error correction. Even though Continuous Variable QKD has seen some significant advancements, there hasn't been much effort to integrate these advancements to make the CVQKD system stronger. By combining discrete modulation, the use of decoy states with the combination of cascade reconciliation and effective polar code-based error correction, our work aims to make the CVQKD more feasible for practical implementation and offer a secure, accurate, and noise-resistant Q KD protocol.

DOI
10.1109/ictp60248.2023.10490525

Related papers

Practical continuous-variable quantum key distribution with composable security

Nitin Jain, Hou-Man Chin, Hossein Mani +10 more

Abstract A quantum key distribution (QKD) system must fulfill the requirement of universal composability to ensure that any cryptographic application (using the QKD system) is also secure. Furthermore, the theoretical proof responsible for security analysis and key generation should cater to the number N of the distributed quantum states being finite in practice. Continuous-variable (CV) QKD based on coherent states, despite being a suitable candidate for integration in the telecom infrastructure, has so far been unable to demonstrate composability as existing proofs require a rather large N for successful key generation. Here we report a Gaussian-modulated coherent state CVQKD system that is able to overcome these challenges and can generate composable keys secure against collective attacks with N ≈ 2 × 10 8 coherent states. With this advance, possible due to improvements to the security proof and a fast, yet low-noise and highly stable system operation, CVQKD implementations take a significant step towards their discrete-variable counterparts in practicality, performance, and security.

arXiv:2110.09262•Nature Communications•Aug 12, 2022•154 citations

Discrete-Modulated Coherent-State Quantum Key Distribution with Basis-Encoding

Mingxuan Guo, Peng Huang, Le Huang +4 more

Discrete-modulated coherent-state continuous-variable quantum key distribution (DMCS-CVQKD) is of great value for its simple implementation. However, the traditional DMCS-CVQKD scheme cannot tolerate the high channel excess noise and channel loss, compared to the Gaussian-modulated scheme, and its error correction is still difficult. In this paper, we propose a discrete-modulated coherent-state basis-encoding quantum key distribution (DMCS-BE-QKD) protocol, where the secret keys are encoded in the random choice of 2 measurement bases, i.e., the conjugate quadratures X and P of discrete-modulated coherent states, and it only needs simple binary sequence error correction. We analyze the secret key rate of DMCS-BE-QKD protocol under individual and collective attacks in the linear Gaussian channel. The results show that DMCS-BE-QKD can greatly enhance the ability to tolerate the channel loss and excess noise compared to the original DMCS-CVQKD protocol, which can tolerate approximately 40 dB more channel loss compared to the original DMCS-CVQKD for the realistic value of noise. Finally, a proof-of-principle experiment is conducted under a 50.5-km optical fiber to verify the feasibility of DMCS-BE-QKD. It is based on the consistent physical procedures of the traditional DMCS-CVQKD, which makes it perfectly compatible to deployed terminals and can serve as a multiplier for the practical secure quantum cryptography communication in harsh environments.

Research•Jan 1, 2025•4 citations

Free space continuous variable Quantum Key Distribution with discrete phases

Anju Rani, Pooja Chandravanshi, Jayanth Ramakrishnan +6 more

Quantum Key Distribution (QKD) offers unconditional security in principle. Many QKD protocols have been proposed and demonstrated to ensure secure communication between two authenticated users. Continuous variable (CV) QKD offers many advantages over discrete variable (DV) QKD since it is cost-effective, compatible with current classical communication technologies, efficient even in daylight, and gives a higher secure key rate. Keeping this in view, we demonstrate a discrete modulated CVQKD protocol in the free space which is robust against polarization drift. We also present the simulation results with a noise model to account for the channel noise and the effects of various parameter changes on the secure key rate. These simulation results help us to verify the experimental values obtained for the implemented CVQKD.

arXiv:2305.13126•Physics Open•Jul 1, 2023•9 citations

Improving Continuous-Variable Quantum Key Distribution with Shannon-Kotel'nikov Maps

Edmar Nascimento, Francisco de Assis

We propose a continuous-variable quantum key distribution (CVQKD) protocol that uses a Shannon- Kotel'nikov expansion map for preparing coherent states. This kind of mapping acts like an analog error correcting code that improves the fidelity between the source signal and the reconstructed one at the receiver. It is well known that a limitation for extending CVQKD to larger distances is the reconciliation efficiency. Such lack of efficiency in reconciliation is mainly due to the difficulty of finding good error correcting codes for low signal-to-noise ratios. Having this limitation in mind, our protocol allows increasing the signal-to-noise ratio between Alice and Bob, thus making reconciliation easier.

IEEE Globecom Workshops (GC Wkshps)•Dec 1, 2016•1 citation

Experimental demonstration of continuous-variable quantum key distribution over 80 km of standard telecom fiber

Paul Jouguet, Sébastien Kunz-Jacques, Anthony Leverrier +2 more

Summary form only given. Continuous-variable quantum key distribution (CVQKD) is a promising alternative to commonly used discrete-variable QKD protocols, because this technology can be implemented with standard telecom components and recent results suggest that it will be compatible with standard wavelength division multiplexed telecommunication networks [1]. Security proofs against general eavesdropping attacks are available for CVQKD protocols using Gaussian modulation [2], and field implementations over deployed telecommunication networks have been demonstrated over the past few years [3].Long-distance operation of CVQKD systems, however, has been hindered until now by the limited efficiency of the complex error-correction (or reconciliation) algorithms that are required to extract the secret key from the correlated data shared by Alice and Bob. We have designed high-efficiency error correcting-codes [4] allowing to extract an errorless secret key in a CVQKD protocol using a Gaussian modulation of coherent states and a homodyne detection system. These codes are available for a wide range of signal-to-noise ratios on a Gaussian noise channel with a binary modulation and can be combined with a multidimensional reconciliation method [5]. This improved reconciliation procedure considerably extends the secure range of a continuous-variable quantum key distribution with Gaussian modulation.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•May 1, 2013•8 citations

Long-distance continuous-variable measurement-device-independent quantum key distribution with discrete modulation

Hongxin Ma, Peng Huang, Dongyun Bai +4 more

We propose a long-distance continuous-variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol with discrete modulation. This kind of discrete-modulated scheme has good compatibility with efficient error correction code, which leads to higher reconciliation efficiency even at low signal-to-noise ratio. Security analysis shows that the proposed protocol is secure against arbitrary collective attacks in the asymptotic limit with the proper use of decoy states. With the use of discrete modulation, the proposed CV-MDI-QKD protocol has simpler implementation and outperforms previous protocols in terms of achievable maximal transmission distance, which precisely solved the bottleneck of the original Gaussian-modulated CV-MDI-QKD protocol.

arXiv:1812.05254•Physical Review A•Feb 20, 2019•65 citations
As the possibility of a genuine, functioning quantum computer becomes closer to reality every day, so does the urge to use the principles of quantum physics to improve the security of communications. One of the most studied areas of quantum communication is quantum key distribution (QKD), however there are still challenges to overcome, such as low detection accuracy, the need for extensive computation, and the lack of extremely efficient error correction. Even though Continuous Variable QKD has seen some significant advancements, there hasn't been much effort to integrate these advancements to make the CVQKD system stronger. By combining discrete modulation, the use of decoy states with the combination of cascade reconciliation and effective polar code-based error correction, our work aims to make the CVQKD more feasible for practical implementation and offer a secure, accurate, and noise-resistant Q KD protocol.
Abstract A quantum key distribution (QKD) system must fulfill the requirement of universal composability to ensure that any cryptographic application (using the QKD system) is also secure. Furthermore, the theoretical proof responsible for security analysis and key generation should cater to the number N of the distributed quantum states being finite in practice. Continuous-variable (CV) QKD based on coherent states, despite being a suitable candidate for integration in the telecom infrastructure, has so far been unable to demonstrate composability as existing proofs require a rather large N for successful key generation. Here we report a Gaussian-modulated coherent state CVQKD system that is able to overcome these challenges and can generate composable keys secure against collective attacks with N ≈ 2 × 10 8 coherent states. With this advance, possible due to improvements to the security proof and a fast, yet low-noise and highly stable system operation, CVQKD implementations take a significant step towards their discrete-variable counterparts in practicality, performance, and security.
Discrete-modulated coherent-state continuous-variable quantum key distribution (DMCS-CVQKD) is of great value for its simple implementation. However, the traditional DMCS-CVQKD scheme cannot tolerate the high channel excess noise and channel loss, compared to the Gaussian-modulated scheme, and its error correction is still difficult. In this paper, we propose a discrete-modulated coherent-state basis-encoding quantum key distribution (DMCS-BE-QKD) protocol, where the secret keys are encoded in the random choice of 2 measurement bases, i.e., the conjugate quadratures X and P of discrete-modulated coherent states, and it only needs simple binary sequence error correction. We analyze the secret key rate of DMCS-BE-QKD protocol under individual and collective attacks in the linear Gaussian channel. The results show that DMCS-BE-QKD can greatly enhance the ability to tolerate the channel loss and excess noise compared to the original DMCS-CVQKD protocol, which can tolerate approximately 40 dB more channel loss compared to the original DMCS-CVQKD for the realistic value of noise. Finally, a proof-of-principle experiment is conducted under a 50.5-km optical fiber to verify the feasibility of DMCS-BE-QKD. It is based on the consistent physical procedures of the traditional DMCS-CVQKD, which makes it perfectly compatible to deployed terminals and can serve as a multiplier for the practical secure quantum cryptography communication in harsh environments.
Quantum Key Distribution (QKD) offers unconditional security in principle. Many QKD protocols have been proposed and demonstrated to ensure secure communication between two authenticated users. Continuous variable (CV) QKD offers many advantages over discrete variable (DV) QKD since it is cost-effective, compatible with current classical communication technologies, efficient even in daylight, and gives a higher secure key rate. Keeping this in view, we demonstrate a discrete modulated CVQKD protocol in the free space which is robust against polarization drift. We also present the simulation results with a noise model to account for the channel noise and the effects of various parameter changes on the secure key rate. These simulation results help us to verify the experimental values obtained for the implemented CVQKD.
We propose a continuous-variable quantum key distribution (CVQKD) protocol that uses a Shannon- Kotel'nikov expansion map for preparing coherent states. This kind of mapping acts like an analog error correcting code that improves the fidelity between the source signal and the reconstructed one at the receiver. It is well known that a limitation for extending CVQKD to larger distances is the reconciliation efficiency. Such lack of efficiency in reconciliation is mainly due to the difficulty of finding good error correcting codes for low signal-to-noise ratios. Having this limitation in mind, our protocol allows increasing the signal-to-noise ratio between Alice and Bob, thus making reconciliation easier.
Summary form only given. Continuous-variable quantum key distribution (CVQKD) is a promising alternative to commonly used discrete-variable QKD protocols, because this technology can be implemented with standard telecom components and recent results suggest that it will be compatible with standard wavelength division multiplexed telecommunication networks [1]. Security proofs against general eavesdropping attacks are available for CVQKD protocols using Gaussian modulation [2], and field implementations over deployed telecommunication networks have been demonstrated over the past few years [3].Long-distance operation of CVQKD systems, however, has been hindered until now by the limited efficiency of the complex error-correction (or reconciliation) algorithms that are required to extract the secret key from the correlated data shared by Alice and Bob. We have designed high-efficiency error correcting-codes [4] allowing to extract an errorless secret key in a CVQKD protocol using a Gaussian modulation of coherent states and a homodyne detection system. These codes are available for a wide range of signal-to-noise ratios on a Gaussian noise channel with a binary modulation and can be combined with a multidimensional reconciliation method [5]. This improved reconciliation procedure considerably extends the secure range of a continuous-variable quantum key distribution with Gaussian modulation.
We propose a long-distance continuous-variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol with discrete modulation. This kind of discrete-modulated scheme has good compatibility with efficient error correction code, which leads to higher reconciliation efficiency even at low signal-to-noise ratio. Security analysis shows that the proposed protocol is secure against arbitrary collective attacks in the asymptotic limit with the proper use of decoy states. With the use of discrete modulation, the proposed CV-MDI-QKD protocol has simpler implementation and outperforms previous protocols in terms of achievable maximal transmission distance, which precisely solved the bottleneck of the original Gaussian-modulated CV-MDI-QKD protocol.