Amplitude-boosting attack against practical discrete-modulated continuous-variable quantum key distribution

Area of Science:

• Quantum communication security
• Information theory
• Applied physics

Background:

• Discrete-modulated continuous-variable quantum key distribution (DMCV-QKD) offers practical advantages for deployment.
• Its security analysis differs from Gaussian-modulated protocols, posing unique challenges.
• Existing security assessments may not fully cover DMCV-QKD vulnerabilities.

Purpose of the Study:

• To investigate the amplitude-boosting attack against DMCV-QKD systems.
• To assess the impact of this attack on system performance and security.
• To propose countermeasures for enhancing the practical security of DMCV-QKD.

Main Methods:

• Theoretical analysis of the amplitude-boosting attack.
• Simulation of attack scenarios on DMCV-QKD systems.
• Evaluation of secret key rate estimation under attack.

Main Results:

• The amplitude-boosting attack can lead to an overestimation of the secret key rate.
• This overestimation creates a security loophole, potentially more severe than in Gaussian-modulated systems.
• The vulnerability is dependent on specific system parameters and attack strategies.

Conclusions:

• DMCV-QKD systems are vulnerable to amplitude-boosting attacks, necessitating careful security parameter estimation.
• Defensive countermeasures are crucial for mitigating these vulnerabilities and ensuring practical security.
• Further research is needed to fully understand and address the security landscape of DMCV-QKD.