论文标题
量子键分配系统中通过公共渠道通过公共渠道进行时间戳共享的加密安全问题
Cryptographic Security Concerns on Timestamp Sharing via Public Channel in Quantum Key Distribution Systems
论文作者
论文摘要
已知量子密钥分布协议对侧通道攻击很容易受到攻击，该侧通道攻击利用用于获得钥匙位的检测器响应的时间差。针对此计时侧通道攻击的建议解决方案是使用大的时间箱宽度，而不是高分辨率计时信息。常见的概念是，使用较大的垃圾箱宽度会降低检测器响应的分辨率，因此据说可以最大程度地减少对窃听器的信息泄漏。我们挑战了这种传统的观点，并证明增加垃圾箱宽度并不能单调减少关键位与窃听者对探测器响应的观察之间的相互信息。它不应随机增加垃圾箱宽度，而应仔细选择，因为相互信息相对于垃圾箱宽度波动。我们还研究了检测器响应对互信息的全宽度最大值（FWHM）的影响，并表明减少FWHM会增加相互信息。最后，套在一起的开始时间也被证明在封装过程中很重要，并且相互信息会定期波动。
Quantum key distribution protocols are known to be vulnerable against a side channel attack that exploits the time difference in detector responses used to obtain key bits. The recommended solution against this timing side channel attack is to use a large time bin width instead of high resolution timing information. Common notion is that using a large bin width reduces the resolution of detector responses, hence supposedly minimizes the information leakage to an eavesdropper. We challenge this conventional wisdom, and demonstrate that increasing the bin width does not monotonically reduce the mutual information between the key bits and the eavesdropper's observation of detector responses. Instead of randomly increasing the bin width, it should be carefully chosen because the mutual information fluctuates with respect to the bin width. We also examined the effect of full width half maximums (FWHMs) of the detectors responses on the mutual information and showed that decreasing the FWHM increases the mutual information. Lastly, the start time of binning is also shown to be important in binning process and the mutual information fluctuates periodically with respect to it.
