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

@article{Zhao2007ExperimentalDO,
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},
year={2007}
}
• Yi Zhao
• Published 24 April 2007
• Physics
• 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…
329 Citations

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## References

SHOWING 1-10 OF 11 REFERENCES

• Ser. 36, 98
• 2006

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

• Phys . Rev . Lett .

### Phys

• Rev. A 74, 022313
• 2006

• 372
• 2007

### Quant

• Info. Compu. 5, 413
• 2005

### Phys

• 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

### Phys

• Rev. Lett. 67, 661
• 1991

### Phys

• 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