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Autour des réseaux quantiques et des modèles de relais pour la clé quantique

Quoc Cuong Le

Published Jan 1, 2009• 0 citations
OpenAlex

Abstract

Quantum Key Distribution (QKD) is a technology that ensures, in theory, the inviolability of the transmitted key. However, some practical implementation problems remain open, especially on increasing the range of QKD's application. The objective of this thesis is to answer twocorrelated questions: (1) how to build large QKD networks, (2) how to secure QKD key relays. We have proposed, at the first stage, a model to ensure the security of key transmission in a large QKD network by using a stochastic routing. The effectiveness of this method is demonstrated by using percolation theory. In a second stage, we explored the safety of QKD relays and arrive to propose four new models to expand the range of QKD.

Related papers

On the QKD relaying models and building QKD networks

Quoc‐Cuong Le

La distribution de clé quantique (QKD Quantum Key Distribution) est une technologie permettant d assurer au niveau théorique l inviolabilité des clés transmises. Cependant, certains problèmes d ordre pratique de mise en œuvre restent ouverts, en particulier, concernant l augmentation de la portée d application de QKD. L objectif de la thèse est de répondre aux deux questions colérées suivantes : (1) comment de construire des réseaux QKD de grande taille; (2) comment sécuriser les relais des clés QKD. Nous avons proposé, dans un premier temps, un modèle permettant de garantir la sécurité de la transmission de clés dans un réseau QKD de grande taille en utilisant un routage stochastique. L efficacité de ce procédé est démontrée à l aide de la théorie de la percolation. Dans un deuxième temps, nous avons exploré la sécurité des modèles de relais des clés QKD et arrivons à proposer quatres nouveaux modèles capables à étendre la portée de QKD.

•Oct 1, 2009•0 citations

Quantum Relay Nodes: Enhancing Security and Scalability in Quantum Key Distribution Networks

Abhijit Dey, Sujit Biswas, Saikat Bose +1 more

Quantum Key Distribution (QKD) has emerged as a promising technology for secure the communication because its security is achieved through the physical laws of quantum mechanics, rather than being based on mathematical problems. In most of the earlier implementations, QKD relied on the direct exchange of the secret keys between two users. Once implemented in a practical system outside of a controlled laboratory setting, QKD experiences complications associated with the limited distances, communication losses, and vulnerabilities to eavesdropping in the multi-user network configurations, compromising its ability to be this third-generation secure communication system. In this work, we show how quantum relay nodes can be implemented as points along a QKD network. The relay nodes provide additional advantages such as extending the communication distances, increasing eavesdropping resistance and allowing for more sophisticated configurations. While relying on theoretical models and experimentally motivated studies, this paper discusses advantages of implementing a relay architecture into a QKD network and highlights technical difficulties that need to be addressed prior to widespread implementation.

CRC Press eBooks•Sep 3, 2026•0 citations

Using Quantum Key Distribution for Securing Real-Time Applications

Miralem Mehić

Quantum Key Distribution (QKD), based on the laws of physics rather than the computational \ncomplexity of mathematical problems, provides a secure way of establishing symmetrical binary \nkeys between two geographically distant users. The keys are secure from eavesdropping during \ntransmission and QKD ensures that any third party’s knowledge of the key is reduced to a \nminimum. In recent years, a noticeable progress in the development of quantum equipment has \nbeen reflected through a number of successful demonstrations of QKD technology. While they \nshow the great achievements of QKD, many practical difficulties still need to be resolved, such as \nto provide better service differentiation. These networks are characterized as being multihop in \nnature where the consumption key rate is often higher than the charging key rate, which means that \nthe links are available for a limited period of time only. Such features impose several challenges \non the effective modeling and evaluation of reliability as well as finding appropriate Quality \nof Service (QoS) solution. This thesis focuses on research in the field of QKD for securing \nreal-time communication by supporting QoS in QKD networks including a novel QoS model \nand novel distributed reactive routing protocol to achieve high-level scalability and minimize the \nconsumption of key material used for securing routing data. \nAs research in QKD networks grows larger and more complex, the need for highly accurate and \nscalable simulation technologies becomes important to assess the practical feasibility and foresee \ndifficulties in the practical implementation of theoretical achievements. Due to the specificity of \nQKD link which requires optical/quantum and Internet connection between the network nodes, it \nis very costly to deploy a complete testbed containing multiple network hosts and links to validate \nand verify a certain network algorithm or protocol. The network simulators in these circumstances \nsave a lot of money and time in accomplishing such task. A simulation environment offers the \ncreation of complex network topologies, a high degree of control and repeatable experiments, \nwhich in turn allows researchers to conduct exactly the same experiments and confirm their results. \nThis thesis describes the design and implementation of QKD network simulation module which \nwas developed in the network simulator of version 3 (NS-3). The module supports simulation \nof QKD network in overlay mode or in a single TCP/IP mode. Therefore, it can be used for \nsimulation of other network technologies regardless of QKD. \nImplemented simulation model was used for verification of proposed QoS solution. A number \nof simulations were performed. The obtained data have confirmed the primary thesis of this study, \nthat it is possible to use real-time applications in QKD networks.

•Jan 1, 2017•0 citations

Security Analysis of Stochastic Routing Scheme in Grid‐Shaped Partially‐Trusted Relay Quantum Key Distribution Network

Xingtong Liu, Jian Wang, Ruilin Li +1 more

Quantum key distribution (QKD) technology provides proved unconditional security in pointto-point key transmissions based on quantum mechanics. However, several limitations, most prominently range, make it complex to construct large QKD network. The trusted relay QKD network is the most practical scene, and stochastic routing scheme was proposed to solve the fatal problem that some relay nodes may be controlled by adversary. But most results in stochastic routing scheme hinge on an adversary model without consideration of attacker's prior-knowledge and attack strategy. To reveal the security problem, we propose a new adversary model and apply it in grid-shaped partially-trusted relay QKD network. Then we analyze the best attack strategy and the impact on security under various situations respectively. Analysis and simulation results show that in some cases the security of stochastic routing scheme will be compromised, and a generalized upper bound for the overall safe probability is obtained. We also discuss how to alleviate the security problem, making the network more robust to attacks.

Chinese Journal of Electronics•Mar 1, 2018•3 citations

The security of practical quantum key distribution

Valerio Scarani, Helle Bechmann-Pasquinucci, Nicolas J. Cerf +3 more

Quantum key distribution (QKD) is the first quantum information task to reach the level of mature technology, already fit for commercialization. It aims at the creation of a secret key between authorized partners connected by a quantum channel and a classical authenticated channel. The security of the key can in principle be guaranteed without putting any restriction on an eavesdropper's power. This article provides a concise up-to-date review of QKD, biased toward the practical side. Essential theoretical tools that have been developed to assess the security of the main experimental platforms are presented (discrete-variable, continuous-variable, and distributed-phase-reference protocols).

arXiv:0802.4155•Reviews of Modern Physics•Sep 29, 2009•3,747 citations

Quantum key distribution in partially-trusted QKD ring networks

Xinyi Lin, Gonghua Hou, Wei Lin +1 more

The long-distance transmission of quantum secret key is a challenge for quantum communication. As far as the current relay technology is concerned, the trusted relay technology is a more practical scheme. However, the trusted relay technology requires every relay node to be trusted, but in practical applications, the security of some relay nodes cannot be guaranteed. How to overcome the security problem of trusted relay technology and realize the security key distribution of remote quantum network has become a new problem. Therefore, in this paper, a method of quantum key distribution in ring network is proposed under the condition of the coexistence of trusted and untrusted repeaters, and proposes a partially-trusted based routing algorithm (PT-RA). This scheme effectively solves the security problem of key distribution in ring backbone network. And simulation results show that PT-RA can significantly improve key distribution success rate compared with the original trusted relay technology.

IEEE International Conference on Information Systems and Computer Aided Education (ICISCAE)•Sep 27, 2020•9 citations
Quantum Key Distribution (QKD) is a technology that ensures, in theory, the inviolability of the transmitted key. However, some practical implementation problems remain open, especially on increasing the range of QKD's application. The objective of this thesis is to answer twocorrelated questions: (1) how to build large QKD networks, (2) how to secure QKD key relays. We have proposed, at the first stage, a model to ensure the security of key transmission in a large QKD network by using a stochastic routing. The effectiveness of this method is demonstrated by using percolation theory. In a second stage, we explored the safety of QKD relays and arrive to propose four new models to expand the range of QKD.
La distribution de clé quantique (QKD Quantum Key Distribution) est une technologie permettant d assurer au niveau théorique l inviolabilité des clés transmises. Cependant, certains problèmes d ordre pratique de mise en œuvre restent ouverts, en particulier, concernant l augmentation de la portée d application de QKD. L objectif de la thèse est de répondre aux deux questions colérées suivantes : (1) comment de construire des réseaux QKD de grande taille; (2) comment sécuriser les relais des clés QKD. Nous avons proposé, dans un premier temps, un modèle permettant de garantir la sécurité de la transmission de clés dans un réseau QKD de grande taille en utilisant un routage stochastique. L efficacité de ce procédé est démontrée à l aide de la théorie de la percolation. Dans un deuxième temps, nous avons exploré la sécurité des modèles de relais des clés QKD et arrivons à proposer quatres nouveaux modèles capables à étendre la portée de QKD.
Quantum Key Distribution (QKD) has emerged as a promising technology for secure the communication because its security is achieved through the physical laws of quantum mechanics, rather than being based on mathematical problems. In most of the earlier implementations, QKD relied on the direct exchange of the secret keys between two users. Once implemented in a practical system outside of a controlled laboratory setting, QKD experiences complications associated with the limited distances, communication losses, and vulnerabilities to eavesdropping in the multi-user network configurations, compromising its ability to be this third-generation secure communication system. In this work, we show how quantum relay nodes can be implemented as points along a QKD network. The relay nodes provide additional advantages such as extending the communication distances, increasing eavesdropping resistance and allowing for more sophisticated configurations. While relying on theoretical models and experimentally motivated studies, this paper discusses advantages of implementing a relay architecture into a QKD network and highlights technical difficulties that need to be addressed prior to widespread implementation.
Quantum Key Distribution (QKD), based on the laws of physics rather than the computational \ncomplexity of mathematical problems, provides a secure way of establishing symmetrical binary \nkeys between two geographically distant users. The keys are secure from eavesdropping during \ntransmission and QKD ensures that any third party’s knowledge of the key is reduced to a \nminimum. In recent years, a noticeable progress in the development of quantum equipment has \nbeen reflected through a number of successful demonstrations of QKD technology. While they \nshow the great achievements of QKD, many practical difficulties still need to be resolved, such as \nto provide better service differentiation. These networks are characterized as being multihop in \nnature where the consumption key rate is often higher than the charging key rate, which means that \nthe links are available for a limited period of time only. Such features impose several challenges \non the effective modeling and evaluation of reliability as well as finding appropriate Quality \nof Service (QoS) solution. This thesis focuses on research in the field of QKD for securing \nreal-time communication by supporting QoS in QKD networks including a novel QoS model \nand novel distributed reactive routing protocol to achieve high-level scalability and minimize the \nconsumption of key material used for securing routing data. \nAs research in QKD networks grows larger and more complex, the need for highly accurate and \nscalable simulation technologies becomes important to assess the practical feasibility and foresee \ndifficulties in the practical implementation of theoretical achievements. Due to the specificity of \nQKD link which requires optical/quantum and Internet connection between the network nodes, it \nis very costly to deploy a complete testbed containing multiple network hosts and links to validate \nand verify a certain network algorithm or protocol. The network simulators in these circumstances \nsave a lot of money and time in accomplishing such task. A simulation environment offers the \ncreation of complex network topologies, a high degree of control and repeatable experiments, \nwhich in turn allows researchers to conduct exactly the same experiments and confirm their results. \nThis thesis describes the design and implementation of QKD network simulation module which \nwas developed in the network simulator of version 3 (NS-3). The module supports simulation \nof QKD network in overlay mode or in a single TCP/IP mode. Therefore, it can be used for \nsimulation of other network technologies regardless of QKD. \nImplemented simulation model was used for verification of proposed QoS solution. A number \nof simulations were performed. The obtained data have confirmed the primary thesis of this study, \nthat it is possible to use real-time applications in QKD networks.
Quantum key distribution (QKD) technology provides proved unconditional security in pointto-point key transmissions based on quantum mechanics. However, several limitations, most prominently range, make it complex to construct large QKD network. The trusted relay QKD network is the most practical scene, and stochastic routing scheme was proposed to solve the fatal problem that some relay nodes may be controlled by adversary. But most results in stochastic routing scheme hinge on an adversary model without consideration of attacker's prior-knowledge and attack strategy. To reveal the security problem, we propose a new adversary model and apply it in grid-shaped partially-trusted relay QKD network. Then we analyze the best attack strategy and the impact on security under various situations respectively. Analysis and simulation results show that in some cases the security of stochastic routing scheme will be compromised, and a generalized upper bound for the overall safe probability is obtained. We also discuss how to alleviate the security problem, making the network more robust to attacks.
Quantum key distribution (QKD) is the first quantum information task to reach the level of mature technology, already fit for commercialization. It aims at the creation of a secret key between authorized partners connected by a quantum channel and a classical authenticated channel. The security of the key can in principle be guaranteed without putting any restriction on an eavesdropper's power. This article provides a concise up-to-date review of QKD, biased toward the practical side. Essential theoretical tools that have been developed to assess the security of the main experimental platforms are presented (discrete-variable, continuous-variable, and distributed-phase-reference protocols).
The long-distance transmission of quantum secret key is a challenge for quantum communication. As far as the current relay technology is concerned, the trusted relay technology is a more practical scheme. However, the trusted relay technology requires every relay node to be trusted, but in practical applications, the security of some relay nodes cannot be guaranteed. How to overcome the security problem of trusted relay technology and realize the security key distribution of remote quantum network has become a new problem. Therefore, in this paper, a method of quantum key distribution in ring network is proposed under the condition of the coexistence of trusted and untrusted repeaters, and proposes a partially-trusted based routing algorithm (PT-RA). This scheme effectively solves the security problem of key distribution in ring backbone network. And simulation results show that PT-RA can significantly improve key distribution success rate compared with the original trusted relay technology.