Counteracting a Saturation Attack in Continuous-Variable Quantum Key Distribution Using an Adjustable Optical Filter Embedded in Homodyne Detector

A saturation attack can be employed for compromising the practical security of continuous-variable quantum key distribution (CVQKD). In this paper, we suggest a countermeasure approach to resisting this attack by embedding an adjustable optical filter (AOF) in the CVQKD system. Numerical simulations illustrate the effects of the AOF-enabled countermeasure on the performance in terms of the secret key rate and transmission distance. The legal participants can trace back the information that has been eavesdropped by an attacker from the imperfect receiver, which indicates that this approach can be used for defeating a saturation attack in practical quantum communications.

Automated summary

This paper suggests a countermeasure approach to resist saturation attacks in continuous-variable quantum key distribution (CVQKD) by embedding an adjustable optical filter (AOF) in the system. Numerical simulations demonstrate the positive effects of this approach on the system performance and the ability to trace back eavesdropped information.