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

Physical Review A

Multibit quantum digital signature with continuous variables using basis encoding over insecure channels

Wei Zhao, Ronghua Shi, Jinjing Shi, Peng Huang, Ying Guo, Duan Huang

Published Jan 14, 2021• 23 citations
Publisher

Abstract

A quantum digital signature (QDS) is utilized to authenticate classical messages and offers information theoretical security guaranteed by the laws of quantum mechanics. Focusing on signing a one-bit message, previous continuous-variable quantum digital signature (CV-QDS) protocols that shared secret keys are generated by quantum key distribution, and it is only mentioned to suitably iterate the one-bit protocol for a multibit message. Although the CV-QDS protocol is unconditionally secure while sending single-bit messages, iterating the one-bit protocol in a naive way will allow some forgery attacks. In this paper, for signing one-bit and multibit messages, a CV-QDS protocol is proposed, on the condition that nonrepudiation and no forging are guaranteed. For one-bit and multibit schemes, we compare the difference in the distribution stage and messaging stage, analyzing the security as well as summarizing some formulas for calculation. We hope the protocol with continuous variables could further improve the performance of QDS.

DOI
10.1103/physreva.103.012410

Related papers

High-efficiency continuous-variable quantum digital signature protocol for signing multi-bit messages

Wei Zhao, Ronghua Shi, Xinchao Ruan

Abstract A quantum digital signature (QDS) is guaranteed by the laws of quantum physics and can provide unconditional security to authenticate classical messages. Previous QDS protocols that shared secret keys could be realized using discrete-variable quantum key distribution (DV-QKD), for which the DV-QKD relied on extreme requirements like single-photon detection and extremely weak pulses of light. QDS protocols are mainly focused on how to sign a one-bit message rather than multi-bit messages. In this paper, we present a continuous-variable quantum digital signature (CV-QDS) protocol for signing multi-bit messages. The CV-QDS protocol has better compatibility with existing communication systems and the encoding strategy for multi-bit messages is simpler than before. We hope the continuous-variable protocol could further improve the performance of QDS.

Laser Physics Letters•Jan 29, 2021•2 citations

Teleportation-based continuous-variable quantum digital signature

Wei Zhao, Fuqiang Wang, Yiyu Mao +3 more

In this paper, a continuous-variable quantum digital signature (CV-QDS) protocol based on quantum teleportation (QT) is proposed, and the corresponding theoretical analysis method is established. Unlike previous schemes, we use squeezed states to carry key and secret information about the teleported states that are transmitted through classical and entangled channels without infinite squeezing. In addition, for multibit information signatures, we propose to use the mean and modulation variance of the teleported quantum state to distinguish signatures, and each of which is marked and ordered. In particular, we derive the fidelity that the protocol can achieve, displaying the effectiveness of the method at different compression levels. Security analysis demonstrates that the protocol possesses unforgeability, non-repudiation and robustness, which is suitable for signing one-bit and multibit messages.

Results in Physics•Sep 23, 2023•5 citations

Continuous-variable quantum digital signatures that can withstand coherent attacks

Yi-Fan Zhang, Wen-Bo Liu, Bing-Hong Li +2 more

Quantum digital signatures (QDSs), which utilize correlated bit strings among sender and recipients, guarantee the authenticity, integrity, and nonrepudiation of classical messages based on quantum laws. Continuous-variable (CV) quantum protocol with heterodyne and homodyne measurement has obvious advantages of low-cost implementation and easy wavelength division multiplexing. However, security analyses in previous research are limited to the proof against collective attacks in finite-size scenarios. Moreover, existing multibit CV QDS schemes have primarily focused on adapting single-bit protocols for simplicity of security proof, often sacrificing signature efficiency. Here, we introduce a CV QDS protocol designed to withstand general coherent attacks through the use of a cutting-edge fidelity test function, while achieving high signature efficiency by employing a refined one-time universal hashing signing technique. Our protocol is proved to be robust against finite-size effects and excess noise in quantum channels. In simulation, results demonstrate a significant reduction of over six orders of magnitude in signature length for a megabit message signing task compared with existing CV QDS protocols and this advantage expands as the message size grows. Our work offers a solution with enhanced security and efficiency, paving the way for large-scale deployment of CV QDSs in future quantum networks.

arXiv:2407.03609•Physical Review A•Nov 20, 2024•8 citations

Security of quantum digital signatures for classical messages

Tian‐Yin Wang, Xiao‐Qiu Cai, Yanli Ren +1 more

Quantum digital signatures can be used to authenticate classical messages in an information-theoretically secure way. Previously, a novel quantum digital signature for classical messages has been proposed and gave an experimental demonstration of distributing quantum digital signatures from one sender to two receivers. Some improvement versions were subsequently presented, which made it more feasible with present technology. These proposals for quantum digital signatures are basic building blocks which only deal with the problem of sending single bit messages while no-forging and non-repudiation are guaranteed. For a multi-bit message, it is only mentioned that the basic building blocks must be iterated, but the iteration of the basic building block still does not suffice to define the entire protocol. In this paper, we show that it is necessary to define the entire protocol because some attacks will arise if these building blocks are used in a naive way of iteration. Therefore, we give a way of defining an entire protocol to deal with the problem of sending multi-bit messages based on the basic building blocks and analyse its security.

Scientific Reports•Mar 18, 2015•71 citations

Continuous-variable quantum digital signatures over insecure channels

Matthew Thornton, H. E. Scott, Callum Croal +1 more

Digital signatures ensure the integrity of a classical message and the authenticity of its sender. Despite their far-reaching use in modern communication, currently used signature schemes rely on computational assumptions and will be rendered insecure by a quantum computer. We present a quantum digital signatures (QDS) scheme whose security is instead based on the impossibility of perfectly and deterministically distinguishing between quantum states. Our continuous-variable (CV) scheme relies on phase measurement of a distributed alphabet of coherent states and allows for secure message authentication against a quantum adversary performing collective beamsplitter and entangling-cloner attacks. Crucially, in the CV setting we allow for an eavesdropper on the quantum channels and yet retain shorter signature lengths than previous protocols with no eavesdropper. This opens up the possibility to implement CV QDS alongside existing CV quantum key distribution platforms with minimal modification.

arXiv:1812.09749•Physical Review A•Mar 25, 2019•28 citations

Quantum digital signature with unidimensional continuous-variable against the measurement angular error

Wei Zhao, Ronghua Shi, Xiao-Ming Wu +2 more

The continuous-variable quantum digital signature (CV-QDS) scheme relies on the components of quantum key generation protocol (KGP) to negotiate classical signature, which is more compatible with optical fibers. Nevertheless, the measurement angular error of heterodyne detection or homodyne detection will cause security issues when performing KGP in the distribution stage. For that, we propose to utilize unidimensional modulation in KGP components, which only requires to modulate single quadrature and without the process of basis choice. Numerical simulation results show that the security under collective attack, repudiation attack and forgery attack can be guaranteed. We expect that the unidimensional modulation of KGP components could further simplify the implementation of CV-QDS and circumvent the security issues caused by the measurement angular error.

Optics Express•Apr 24, 2023•7 citations
A quantum digital signature (QDS) is utilized to authenticate classical messages and offers information theoretical security guaranteed by the laws of quantum mechanics. Focusing on signing a one-bit message, previous continuous-variable quantum digital signature (CV-QDS) protocols that shared secret keys are generated by quantum key distribution, and it is only mentioned to suitably iterate the one-bit protocol for a multibit message. Although the CV-QDS protocol is unconditionally secure while sending single-bit messages, iterating the one-bit protocol in a naive way will allow some forgery attacks. In this paper, for signing one-bit and multibit messages, a CV-QDS protocol is proposed, on the condition that nonrepudiation and no forging are guaranteed. For one-bit and multibit schemes, we compare the difference in the distribution stage and messaging stage, analyzing the security as well as summarizing some formulas for calculation. We hope the protocol with continuous variables could further improve the performance of QDS.
Abstract A quantum digital signature (QDS) is guaranteed by the laws of quantum physics and can provide unconditional security to authenticate classical messages. Previous QDS protocols that shared secret keys could be realized using discrete-variable quantum key distribution (DV-QKD), for which the DV-QKD relied on extreme requirements like single-photon detection and extremely weak pulses of light. QDS protocols are mainly focused on how to sign a one-bit message rather than multi-bit messages. In this paper, we present a continuous-variable quantum digital signature (CV-QDS) protocol for signing multi-bit messages. The CV-QDS protocol has better compatibility with existing communication systems and the encoding strategy for multi-bit messages is simpler than before. We hope the continuous-variable protocol could further improve the performance of QDS.
In this paper, a continuous-variable quantum digital signature (CV-QDS) protocol based on quantum teleportation (QT) is proposed, and the corresponding theoretical analysis method is established. Unlike previous schemes, we use squeezed states to carry key and secret information about the teleported states that are transmitted through classical and entangled channels without infinite squeezing. In addition, for multibit information signatures, we propose to use the mean and modulation variance of the teleported quantum state to distinguish signatures, and each of which is marked and ordered. In particular, we derive the fidelity that the protocol can achieve, displaying the effectiveness of the method at different compression levels. Security analysis demonstrates that the protocol possesses unforgeability, non-repudiation and robustness, which is suitable for signing one-bit and multibit messages.
Quantum digital signatures (QDSs), which utilize correlated bit strings among sender and recipients, guarantee the authenticity, integrity, and nonrepudiation of classical messages based on quantum laws. Continuous-variable (CV) quantum protocol with heterodyne and homodyne measurement has obvious advantages of low-cost implementation and easy wavelength division multiplexing. However, security analyses in previous research are limited to the proof against collective attacks in finite-size scenarios. Moreover, existing multibit CV QDS schemes have primarily focused on adapting single-bit protocols for simplicity of security proof, often sacrificing signature efficiency. Here, we introduce a CV QDS protocol designed to withstand general coherent attacks through the use of a cutting-edge fidelity test function, while achieving high signature efficiency by employing a refined one-time universal hashing signing technique. Our protocol is proved to be robust against finite-size effects and excess noise in quantum channels. In simulation, results demonstrate a significant reduction of over six orders of magnitude in signature length for a megabit message signing task compared with existing CV QDS protocols and this advantage expands as the message size grows. Our work offers a solution with enhanced security and efficiency, paving the way for large-scale deployment of CV QDSs in future quantum networks.
Quantum digital signatures can be used to authenticate classical messages in an information-theoretically secure way. Previously, a novel quantum digital signature for classical messages has been proposed and gave an experimental demonstration of distributing quantum digital signatures from one sender to two receivers. Some improvement versions were subsequently presented, which made it more feasible with present technology. These proposals for quantum digital signatures are basic building blocks which only deal with the problem of sending single bit messages while no-forging and non-repudiation are guaranteed. For a multi-bit message, it is only mentioned that the basic building blocks must be iterated, but the iteration of the basic building block still does not suffice to define the entire protocol. In this paper, we show that it is necessary to define the entire protocol because some attacks will arise if these building blocks are used in a naive way of iteration. Therefore, we give a way of defining an entire protocol to deal with the problem of sending multi-bit messages based on the basic building blocks and analyse its security.
Digital signatures ensure the integrity of a classical message and the authenticity of its sender. Despite their far-reaching use in modern communication, currently used signature schemes rely on computational assumptions and will be rendered insecure by a quantum computer. We present a quantum digital signatures (QDS) scheme whose security is instead based on the impossibility of perfectly and deterministically distinguishing between quantum states. Our continuous-variable (CV) scheme relies on phase measurement of a distributed alphabet of coherent states and allows for secure message authentication against a quantum adversary performing collective beamsplitter and entangling-cloner attacks. Crucially, in the CV setting we allow for an eavesdropper on the quantum channels and yet retain shorter signature lengths than previous protocols with no eavesdropper. This opens up the possibility to implement CV QDS alongside existing CV quantum key distribution platforms with minimal modification.
The continuous-variable quantum digital signature (CV-QDS) scheme relies on the components of quantum key generation protocol (KGP) to negotiate classical signature, which is more compatible with optical fibers. Nevertheless, the measurement angular error of heterodyne detection or homodyne detection will cause security issues when performing KGP in the distribution stage. For that, we propose to utilize unidimensional modulation in KGP components, which only requires to modulate single quadrature and without the process of basis choice. Numerical simulation results show that the security under collective attack, repudiation attack and forgery attack can be guaranteed. We expect that the unidimensional modulation of KGP components could further simplify the implementation of CV-QDS and circumvent the security issues caused by the measurement angular error.