【摘要】 考虑强衰减激光脉冲技术实现的准单光子源和量子信道损耗以及窃听者Eve窃听能力有限等实际情况,提出了一种窃听装置;同时对扩展BB84协议的各种窃听做了全面分析,计算得出发送者Alice/窃听者Eve所获得的交互信息量和发送者Alice/接收者Bob所能容忍的误码率上限,以此作为检测量子信道安全性的标准,同时得出Breidbart基/分束攻击相结合的方法是比截取/重发更为有效的窃听方案·更多还原

【Abstract】 It is used attenuated laser pulses as the signal source rather than single photons in practical QKD system. The channels is used to transmit are lossy. Eve′s eavesdropping ability is limited. On the basis of above three points, a eavesdropping device is presented. Meanwhile, the study is analyzed the calculation of the effective average Alice/Eve mutual information and Alice/Bob error rate′s upper limit in six states QKD protocol. It shows that Breidbart eavesdropping/beamsplitter is the more effective one compared with Breidbart eavesdropping (B/B strategy).更多还原