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

Workshop on Recent Advances in Photonics (WRAP)

Security with 3-Pulse Differential Phase Shift Quantum Key Distribution

Shashank Kumar Ranu, Gautam Kumar Shaw, Anil Prabhakar, Prabha Mandayam

Published Dec 1, 2017• 6 citations
Publisher

Abstract

3-pulse DPS-QKD offers enhanced security compared to conventional DPS-QKD by decreasing the learning rate of an eavesdropper and unmasking her presence with an increased error rate upon application of intercept and resend attack. The probability of getting one bit of sifted key information using beamsplitter attack also reduces by 25% in our implentation compared to normal DPS.

DOI
10.1109/wrap.2017.8468572

Related papers

Differential-phase-shift quantum key distribution with intense decoy pulses

Kyo Inoue, Toshimori Honjo

In quantum key distribution (QKD), eavesdropping is generally detected based on bit errors resulting from eavesdropper attacks. This study proposes a QKD scheme for detecting eavesdropping based on the photon-detection rate instead of the bit error rate. The differential-phase-shift (DPS) QKD protocol, which transmits lasting weak coherent pulses, is modified such that decoy pulses with a large mean photon number are randomly inserted into a signal pulse sequence. With this modification, eavesdropping can be detected by monitoring the photon-detection rates at the time slots around the decoy pulses. The key-creation performance of the modified DPS-QKD system is evaluated, and the results indicate that the QKD distance is increased with the modification.

Journal of the Optical Society of America B•Aug 7, 2025•1 citation

Differential-phase-shift quantum key distribution

Kyo Inoue, Hiroki Takesue, Toshimori Honjo

A novel type of quantum key distribution (QKD) protocol, called DPS (differential-phase-shift) QKD, was proposed several years ago. A sender transmits a highly-attenuated coherent pulse train with {0, π} phase, and a receiver receives it with a one-bit delay Mach-Zehnder interferometer followed by photon detectors. A secret key is created from photon detection events, whose security is based on the fact that an eavesdropper cannot perfectly measure the phase information of a highly-attenuated coherent pulse train. This protocol has some features of simple setup, potential for a high key creation rate, and robustness against photon-number-splitting attack. This paper overviews DPS-QKD. The operation mechanism is described, and then some experimental efforts are introduced, featuring use of a glass waveguide Mach-Zehnder interferometer and advanced single-photon detectors. The highest key rate and the longest distance have been achieved with the DPS-QKD protocol. Some modified schemes are also presented, including that utilizing quantum entanglement, that using decoy pulses, and that using macroscopic coherent light.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 9, 2007•3 citations

Differential-phase-shift quantum key distribution with an extended degree of freedom

Toshimori Honjo, Kyo Inoue

Differential-phase-shift quantum key distribution (DPS-QKD) with an extended degree of freedom of measurement is proposed. Extending the degree of freedom makes it possible to strengthen the DPS-QKD scheme against intercept-and-resend attacks. The feasibility of this idea is experimentally demonstrated.

Optics Letters•Feb 15, 2006•9 citations

Differential Phase Encoding Scheme for Measurement-Device-Independent Quantum Key Distribution

Shashank Kumar Ranu, Anil Prabhakar, Prabha Mandayam

This paper proposes a measurement-device-independent quantum key distribution (MDI-QKD) scheme based on differential phase encoding. The differential phase shift MDI-QKD (DPS-MDI-QKD) couples the advantages of DPS-QKD with that of MDI-QKD. The proposed scheme offers resistance against photon number splitting attack and phase fluctuations as well as immunity against detector side-channel vulnerabilities. The design proposed in this paper uses weak coherent pulses in a superposition of three orthogonal states, corresponding to one of three distinct paths in a delay-line interferometer. The classical bit information is encoded in the phase difference between pulses traversing successive paths. This 3-pulse superposition offers enhanced security compared to using a train of pulses by decreasing the learning rate of an eavesdropper and unmasking her presence with an increased error rate upon application of intercept and resend attack and beamsplitter attack. The proposed scheme employs phase locking of the sources of the two trusted parties so as to maintain the coherence between their optical signal, and uses a beamsplitter (BS) at the untrusted node (Charlie) to extract the key information from the phase encoded signals.

National Conference on Communications•Feb 1, 2019•1 citation

An efficient modeling and simulation of differential phase shift-quantum key distribution (DPS-QKD) system using optisystem

Mu'azu Dauda

Differential phase-shift (DPS) quantum key distribution (QKD) is a unique QKD protocol that is different from traditional ones, featuring simplicity and practicality. In this work, we simulated the DPS-QKD experiment conducted by (Liu et al., 2013), using OptiSystem 7. To the best of our knowledge, this is the first simulation work on DPS-QKD using a single photon source.We used a random number generator to get the phase modulation pattern of N=5, 7,9,11 and 13, while for the 3 and 15 pulse cases, the pattern adopted in the experiment was used. When the number of pulse (N) was 3, a quantum bit error rate (QBER) of 3.0%, which is lower than the minimum QBER of 4.12% required for unconditional security, was obtained. The key creation efficiency increases with the increase in the number of pulse up to 15, as it reaches 93.4% but at the expense of the increment in QBER. The result of our simulation is, on some aspect, in agreement with the experimental result. However, we were able to extend the transmission distance from 3 meter, as in the experiment, to 10 meter. The coincidence count obtained was also in total agreement with the one obtained from the experiment. The result of the average QBER indicated that increase in the pulse number N causes the QBER to raise up due to longer rise and fall time of phase modulation step which affect the MZ inference. Therefore, we suggest using a faster waveform generator with shorter rise and fall times will remarkably lower the QBER. Extending the transmission coverage to a longer distance while, at the same time reducing the QBER with full unconditional security will part of the future research.

•Jan 1, 2017•0 citations

DPS Quantum Key Distribution System

Kyo Inoue

Differential-phase-shift (DPS) quantum key distribution (QKD) is one scheme of quantum key distribution whose security is based on the quantum nature of lightwave. This protocol features simplicity, a high key creation rate, and robustness against photon-number-splitting attacks. We describe DPS-QKD in this paper, including its setup and operation, eavesdropping against DPS-QKD, system performance, and modified systems to improve the system performance.

IEICE Transactions on Fundamentals of Electronics Communications and Computer Sciences•Jan 1, 2010•1 citation
3-pulse DPS-QKD offers enhanced security compared to conventional DPS-QKD by decreasing the learning rate of an eavesdropper and unmasking her presence with an increased error rate upon application of intercept and resend attack. The probability of getting one bit of sifted key information using beamsplitter attack also reduces by 25% in our implentation compared to normal DPS.
In quantum key distribution (QKD), eavesdropping is generally detected based on bit errors resulting from eavesdropper attacks. This study proposes a QKD scheme for detecting eavesdropping based on the photon-detection rate instead of the bit error rate. The differential-phase-shift (DPS) QKD protocol, which transmits lasting weak coherent pulses, is modified such that decoy pulses with a large mean photon number are randomly inserted into a signal pulse sequence. With this modification, eavesdropping can be detected by monitoring the photon-detection rates at the time slots around the decoy pulses. The key-creation performance of the modified DPS-QKD system is evaluated, and the results indicate that the QKD distance is increased with the modification.
A novel type of quantum key distribution (QKD) protocol, called DPS (differential-phase-shift) QKD, was proposed several years ago. A sender transmits a highly-attenuated coherent pulse train with {0, π} phase, and a receiver receives it with a one-bit delay Mach-Zehnder interferometer followed by photon detectors. A secret key is created from photon detection events, whose security is based on the fact that an eavesdropper cannot perfectly measure the phase information of a highly-attenuated coherent pulse train. This protocol has some features of simple setup, potential for a high key creation rate, and robustness against photon-number-splitting attack. This paper overviews DPS-QKD. The operation mechanism is described, and then some experimental efforts are introduced, featuring use of a glass waveguide Mach-Zehnder interferometer and advanced single-photon detectors. The highest key rate and the longest distance have been achieved with the DPS-QKD protocol. Some modified schemes are also presented, including that utilizing quantum entanglement, that using decoy pulses, and that using macroscopic coherent light.
This paper proposes a measurement-device-independent quantum key distribution (MDI-QKD) scheme based on differential phase encoding. The differential phase shift MDI-QKD (DPS-MDI-QKD) couples the advantages of DPS-QKD with that of MDI-QKD. The proposed scheme offers resistance against photon number splitting attack and phase fluctuations as well as immunity against detector side-channel vulnerabilities. The design proposed in this paper uses weak coherent pulses in a superposition of three orthogonal states, corresponding to one of three distinct paths in a delay-line interferometer. The classical bit information is encoded in the phase difference between pulses traversing successive paths. This 3-pulse superposition offers enhanced security compared to using a train of pulses by decreasing the learning rate of an eavesdropper and unmasking her presence with an increased error rate upon application of intercept and resend attack and beamsplitter attack. The proposed scheme employs phase locking of the sources of the two trusted parties so as to maintain the coherence between their optical signal, and uses a beamsplitter (BS) at the untrusted node (Charlie) to extract the key information from the phase encoded signals.
Differential phase-shift (DPS) quantum key distribution (QKD) is a unique QKD protocol that is different from traditional ones, featuring simplicity and practicality. In this work, we simulated the DPS-QKD experiment conducted by (Liu et al., 2013), using OptiSystem 7. To the best of our knowledge, this is the first simulation work on DPS-QKD using a single photon source.We used a random number generator to get the phase modulation pattern of N=5, 7,9,11 and 13, while for the 3 and 15 pulse cases, the pattern adopted in the experiment was used. When the number of pulse (N) was 3, a quantum bit error rate (QBER) of 3.0%, which is lower than the minimum QBER of 4.12% required for unconditional security, was obtained. The key creation efficiency increases with the increase in the number of pulse up to 15, as it reaches 93.4% but at the expense of the increment in QBER. The result of our simulation is, on some aspect, in agreement with the experimental result. However, we were able to extend the transmission distance from 3 meter, as in the experiment, to 10 meter. The coincidence count obtained was also in total agreement with the one obtained from the experiment. The result of the average QBER indicated that increase in the pulse number N causes the QBER to raise up due to longer rise and fall time of phase modulation step which affect the MZ inference. Therefore, we suggest using a faster waveform generator with shorter rise and fall times will remarkably lower the QBER. Extending the transmission coverage to a longer distance while, at the same time reducing the QBER with full unconditional security will part of the future research.