Experimental demonstration of time-shift attack against practical quantum key distribution systems

  title={Experimental demonstration of time-shift attack against practical quantum key distribution systems},
  author={Yi Zhao and Chi-Hang Fred Fung and Bing Qi and Christine Chen and Hoi-Kwong Lo},
  journal={Physical Review A},
Quantum-key-distribution (QKD) systems can send quantum signals over more than $100\phantom{\rule{0.3em}{0ex}}\mathrm{km}$ standard optical fiber and are widely believed to be secure. Here, we show experimentally a technologically feasible attack\char22{}namely, the time-shift attack\char22{}against a commercial QKD system. Our result shows that, contrary to popular belief, an eavesdropper, Eve, has a non-negligible probability $(\ensuremath{\sim}4%)$ to break the security of the system. Eve's… 

Figures and Tables from this paper

Quantum hacking: attacking practical quantum key distribution systems

  • B. QiC. Fung H. Lo
  • Physics, Computer Science
    SPIE Optical Engineering + Applications
  • 2007
Two types of eavesdropping attacks against a practical QKD system are reported, including "time-shift" attack, which is applicable toQKD systems with gated single photon detectors (SPDs), and "phase-remapping" attack which exploits the fact that a practical phase modulator has a finite response time.

Experimental demonstration of phase-remapping attack in a practical quantum key distribution system

This paper performs a proof-of-principle experiment to demonstrate a technically feasible 'intercept- and-resend' attack that exploits such a security loophole in a commercial 'plug & play' QKD system.

Security of practical quantum key distribution with weak-randomness basis selection

This work analyzes the security of the practical quantum key distribution system with weak-randomness basis selection, where the basis selection may be partly controlled by the eavesdropper due to the imperfect quantum devices.

Real-world two-photon interference and proof-of-principle quantum key distribution immune to detector attacks.

The first proof-of-principle implementation of a new quantum-key-distribution protocol that is immune to any such attack is reported, and the feasibility of controlled two-photon interference in a real-world environment is established.

Attacking a Measurement Device Independent Practical Quantum-Key-Distribution System with Wavelength-Dependent Beam-Splitter and Multi-Wavelength Sources

It is known that practical quantum key distribution system, because of the imperfect of devices, has sort of loopholes, so Eve can attack through these loopholes. The proposition of measurement

Finite-key analysis for measurement-device-independent quantum key distribution.

This work provides a rigorous security proof against general attacks in the finite-key regime by applying large deviation theory, specifically the Chernoff bound, to perform parameter estimation and demonstrates the feasibility of long-distance implementations of measurement-device-independent quantum key distribution within a reasonable time frame of signal transmission.

Inducing a detector efficiency mismatch to hack a commercial quantum key distribution system

  • N. JainL. Lydersen G. Leuchs
  • Computer Science
    2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)
  • 2011
This work states that Eve, the would-be eavesdropper, could exploit imperfections in Alice's or Bob's equipment remotely, or vulnerabilities in the actual implementation of the abstract QKD protocol.

Improve security of quantum cryptography

Quantum key distribution (QKD) is a method to establish a secret key between two communicating parties, often referred to as Alice and Bob. Should an eavesdropper, Eve, spy on their communication,

Security proof of practical quantum key distribution with detection-efficiency mismatch

The method applies to a variety of coding mechanisms, including time-bin encoding, and also allows for general manipulations of the spatial-temporal modes by the adversary, which can close the long-standing question how to provide a valid, complete security proof of a QKD setup with characterized efficiency mismatch.

Security analysis on some experimental quantum key distribution systems with imperfect optical and electrical devices

The recent work on quantum hacking on some experimental QKD systems with respect to imperfect devices carried out internationally is reviewed and recent hacking works in details are presented, including passive faraday mirror attack, partially random phase attack, wavelength-selected photon-number-splitting attack, frequency shift attack, and single-photon-detector attack.




  • Ser. 36, 98
  • 2006

Science 283 , 2050 ( 1999 ) ; P . Shor and J . Preskill

  • Phys . Rev . Lett .


  • Rev. A 74, 022313
  • 2006

Nature 447

  • 372
  • 2007


  • Info. Compu. 5, 413
  • 2005


  • Rev. Lett. 95, 010503
  • 2005

in Theory of Cryptography: Second Theory of Cryptography Conference

  • TCC 2005, Lecture Notes in Computer Science, edited by J. Kilian
  • 2005


  • Rev. Lett. 67, 661
  • 1991


  • Rev. Lett. 91, 057901 (2003); H.-K. Lo, X. Ma, and K. Chen, Phys. Rev. Lett. 94, 230504 (2005); X.-B. Wang, Phys. Rev. Lett. 94, 230503 (2005); X. Ma, et al., Phys. Rev. A 72, 012326 (2005); X.-B. Wang, Phys. Rev. A 72, 012322
  • 2005

in Proceedings of IEEE International Conference on Computers

  • Systems, and Signal Processing
  • 1984