Unambiguous state discrimination and joint measurement attacks on passive side channel of the light source in BB84 decoy-state protocol

Abstract Quantum key distribution (QKD) has a promise of unconditionally secure communication between the remote sides. The real-world QKD implementations, however, have numerous loopholes, both of engeneering and physical origin, and compromise the security promise. In this work, we investigate two attack strategies on the passive side channel of the light source along with the optimal cloning attack on the BB84 protocol with decoy-states. We calculate an upper bound of a secret key rate for these situations and show that the joint measurement attack on the signal and side channel degree of freedom is more effective to the adversary.

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Security Analysis of Discrete-Modulated Continuous-Variable Quantum Key Distribution over Seawater Channel

Applied Sciences ◽

10.3390/app9224956 ◽

2019 ◽

Vol 9 (22) ◽

pp. 4956 ◽

Cited By ~ 2

Author(s):

Xinchao Ruan ◽

Hang Zhang ◽

Wei Zhao ◽

Xiaoxue Wang ◽

Xuan Li ◽

...

Keyword(s):

Quantum Key Distribution ◽

Secure Communication ◽

Security Analysis ◽

Finite Size ◽

Key Distribution ◽

Continuous Variable ◽

Heterodyne Detection ◽

Secret Key ◽

Transmission Distance ◽

Better Than

We investigate the optical absorption and scattering properties of four different kinds of seawater as the quantum channel. The models of discrete-modulated continuous-variable quantum key distribution (CV-QKD) in free-space seawater channel are briefly described, and the performance of the four-state protocol and the eight-state protocol in asymptotic and finite-size cases is analyzed in detail. Simulation results illustrate that the more complex is the seawater composition, the worse is the performance of the protocol. For different types of seawater channels, we can improve the performance of the protocol by selecting different optimal modulation variances and controlling the extra noise on the channel. Besides, we can find that the performance of the eight-state protocol is better than that of the four-state protocol, and there is little difference between homodyne detection and heterodyne detection. Although the secret key rate of the protocol that we propose is still relatively low and the maximum transmission distance is only a few hundred meters, the research on CV-QKD over the seawater channel is of great significance, which provides a new idea for the construction of global secure communication network.

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DECOY STATE QUANTUM KEY DISTRIBUTION

International Journal of Quantum Information ◽

10.1142/s0219749905001328 ◽

2005 ◽

Vol 03 (supp01) ◽

pp. 143-143 ◽

Cited By ~ 4

Author(s):

HOI-KWONG LO

Keyword(s):

Quantum Key Distribution ◽

Secure Communication ◽

Key Distribution ◽

Generation Rate ◽

Key Generation ◽

Long Distance ◽

Decoy State ◽

Bb84 Protocol ◽

High Loss ◽

Statistical Fluctuations

Quantum key distribution (QKD) allows two parties to communicate in absolute security based on the fundamental laws of physics. Up till now, it is widely believed that unconditionally secure QKD based on standard Bennett-Brassard (BB84) protocol is limited in both key generation rate and distance because of imperfect devices. Here, we solve these two problems directly by presenting new protocols that are feasible with only current technology. Surprisingly, our new protocols can make fiber-based QKD unconditionally secure at distances over 100km (for some experiments, such as GYS) and increase the key generation rate from O(η2) in prior art to O(η) where η is the overall transmittance. Our method is to develop the decoy state idea (first proposed by W.-Y. Hwang in "Quantum Key Distribution with High Loss: Toward Global Secure Communication", Phys. Rev. Lett. 91, 057901 (2003)) and consider simple extensions of the BB84 protocol. This part of work is published in "Decoy State Quantum Key Distribution", . We present a general theory of the decoy state protocol and propose a decoy method based on only one signal state and two decoy states. We perform optimization on the choice of intensities of the signal state and the two decoy states. Our result shows that a decoy state protocol with only two types of decoy states—a vacuum and a weak decoy state—asymptotically approaches the theoretical limit of the most general type of decoy state protocols (with an infinite number of decoy states). We also present a one-decoy-state protocol as a special case of Vacuum+Weak decoy method. Moreover, we provide estimations on the effects of statistical fluctuations and suggest that, even for long distance (larger than 100km) QKD, our two-decoy-state protocol can be implemented with only a few hours of experimental data. In conclusion, decoy state quantum key distribution is highly practical. This part of work is published in "Practical Decoy State for Quantum Key Distribution", . We also have done the first experimental demonstration of decoy state quantum key distribution, over 15km of Telecom fibers. This part of work is published in "Experimental Decoy State Quantum Key Distribution Over 15km", .

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The enhanced measurement-device-independent quantum key distribution with heralded pair coherent state

Modern Physics Letters B ◽

10.1142/s0217984920500633 ◽

2019 ◽

Vol 34 (04) ◽

pp. 2050063

Author(s):

Yefeng He ◽

Wenping Ma

Keyword(s):

Light Source ◽

Error Rate ◽

Quantum Key Distribution ◽

Key Distribution ◽

Generation Rate ◽

Key Generation ◽

Measurement Device ◽

Decoy State ◽

Communication Distance ◽

Measurement Device Independent

With heralded pair coherent states (HPCS), orbital angular momentum (OAM) states and pulse position modulation (PPM) technology, a decoy-state measurement-device-independent quantum key distribution (MDI-QKD) protocol is proposed. OAM states and PPM technology are used to realize the coding of the signal states in the HPCS light source. The use of HPCS light source, OAM coding and PPM coding cannot only reduce the error rate but also improve the key generation rate and communication distance. The new MDI-QKD protocol also employs three-intensity decoy states to avoid the attacks against the light source. By calculating the error rate and key generation rate, the performance of the MDI-QKD protocol is analyzed. Numerical simulation shows that the protocol has very low error rate and very high key generation rate. Moreover, the maximum communication distance can reach 455 km.

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Unambiguous State Discrimination in Quantum Key Distribution Based on Time Coding

Journal of Applied Spectroscopy ◽

10.1007/s10812-019-00897-z ◽

2019 ◽

Vol 86 (5) ◽

pp. 806-809 ◽

Cited By ~ 1

Author(s):

M. M. Eskandari ◽

D. B. Horoshko ◽

S. Ya. Kilin

Keyword(s):

Quantum Key Distribution ◽

Key Distribution ◽

State Discrimination ◽

Time Coding ◽

Unambiguous State Discrimination

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High performance reconciliation for continuous-variable quantum key distribution with LDPC code

International Journal of Quantum Information ◽

10.1142/s0219749915500100 ◽

2015 ◽

Vol 13 (02) ◽

pp. 1550010 ◽

Cited By ~ 22

Author(s):

Dakai Lin ◽

Duan Huang ◽

Peng Huang ◽

Jinye Peng ◽

Guihua Zeng

Keyword(s):

Quantum Key Distribution ◽

Secure Communication ◽

High Speed ◽

High Performance ◽

Graphics Processing Unit ◽

Ldpc Code ◽

Key Distribution ◽

Continuous Variable ◽

Processing Unit ◽

Secret Key

Reconciliation is a significant procedure in a continuous-variable quantum key distribution (CV-QKD) system. It is employed to extract secure secret key from the resulted string through quantum channel between two users. However, the efficiency and the speed of previous reconciliation algorithms are low. These problems limit the secure communication distance and the secure key rate of CV-QKD systems. In this paper, we proposed a high-speed reconciliation algorithm through employing a well-structured decoding scheme based on low density parity-check (LDPC) code. The complexity of the proposed algorithm is reduced obviously. By using a graphics processing unit (GPU) device, our method may reach a reconciliation speed of 25 Mb/s for a CV-QKD system, which is currently the highest level and paves the way to high-speed CV-QKD.

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Quantum Key Distribution Based-on Refraction and Polarization Entanglement

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.f8222.038620 ◽

2020 ◽

Vol 8 (6) ◽

pp. 2911-2918

Keyword(s):

Quantum Key Distribution ◽

Secure Communication ◽

Key Distribution ◽

Public Key ◽

Entangled State ◽

Key Generation ◽

Secret Key ◽

The Public ◽

Encryption And Decryption ◽

Refraction Factor

Cryptography is the specialty of encoding and decoding messages and exists as extended as the individuals have doubted from one another and need secure correspondence. The traditional techniques for encryption naturally depend on any among public key or secret key approaches. In general, the public key encryption depends on two keys, for example, public key and private key. Since encryption and decryption keys are different, it isn't important to safely distribute a key. In this approach, the difficult of the numerical issues is assumed, not demonstrated. All the security will be easily compromised if proficient factoring algorithms are found. In secret key encryption two clients at first create secret key, which is a long string of arbitrarily selected bits and safely shares between them. At that point the clients can utilize the secret key along with the algorithms to encryption and decryption information. The procedures are complicated and also planned such a way that every bit of output is based on every bit of input. There are two fundamental issues with secret key encryption; first one is that by breaking down the openly known encoding algorithms, it gets simpler to decrypt the message. The subsequent one is that it experiences key-conveyance issue. As a result of the ongoing improvements in quantum processing and quantum data hypothesis, the quantum computers presents genuine difficulties to generally utilized current cryptographic strategy. The improvement of quantum cryptography beat the deficiencies of old style cryptography and achieves these huge accomplishments by using the properties of infinitesimal articles, for example, photon with its polarization and entangled state. In this paper, Polarization by refraction based quantum key distribution (PR-QKD) is proposed for quantum key generation and distribution. The proposed work considers three basis of polarization such as rectilinear (horizontal and vertical), circular (left-circular and right-circular), ellipse (left-ellipse and rightellipse) and refraction factor. This quantum key can be used for secure communication between two users who are spatially separated and also offer intrusion detection ability to detect attackers. The theoretical approach and conceptual results are discussed in this paper.

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Decoy-state quantum key distribution with practical light source

Acta Physica Sinica ◽

10.7498/aps.60.110303 ◽

2011 ◽

Vol 60 (11) ◽

pp. 110303

Author(s):

Jiao Rong-Zhen ◽

Zhang Chao ◽

Ma Hai-Qiang

Keyword(s):

Light Source ◽

Quantum Key Distribution ◽

Key Distribution ◽

Decoy State

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Unambiguous State Discrimination Attack on the B92 Protocol of Quantum Key Distribution with Single Photons

Nonlinear Phenomena in Complex Systems ◽

10.33581/1561-4085-2021-24-3-222-229 ◽

2021 ◽

Vol 24 (3) ◽

Author(s):

D. B. Horoshko ◽

S. Ya. Kilin

Keyword(s):

Quantum Key Distribution ◽

Single Photon ◽

Key Distribution ◽

Single Photons ◽

Single Photon Source ◽

Quantum Cloning ◽

State Discrimination ◽

Photon Source ◽

Unambiguous State Discrimination ◽

B92 Protocol

We consider an unambiguous state discrimination attack on the B92 protocol of quantum key distribution, realized on the basis of polarization encoding of photons produced by a single-photon source. We calculate the secure key rate and the maximal tolerable loss for various overlaps between two signal states employed in this protocol. We make also a comparison with a physically impossible attack of perfect quantum cloning, and show that the unambiguous state discrimination is much more dangerous for the B92 protocol, than this attack, demonstrating thus, that the security of quantum key distribution is not always based on the no-cloning theorem.

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