诱骗态量子密钥分发中不可区分假设的合理性和安全性验证

Rationality and Security Verification of Indistinguishability Assumption in Decoy-State Quantum Key Distribution

采用贝叶斯决策来区分单诱骗态量子密钥分发中的信号态和诱骗态。分析结果表明,仍然只能得到信号态和诱骗态拥有相同i光子透射率的结论,从而验证了信号态和诱骗态不可区分这一假设的合理性,也验证了诱骗态方法的安全性。此外,分别对比单信号态和信号态+单诱骗态两种情况下光子数分离攻击前后的安全密钥率,发现前者攻击成功,后者攻击失败,这证明了诱骗态存在的必要性,验证了诱骗态方法确实能够抵抗光子数分离攻击,同时也进一步验证了诱骗态方法的安全性。

In this paper, we use Bayesian decision to distinguish signal state from decoy state in one decoystate quantum key distribution. The analysis results show that we can still only get the conclusion that the signal state and decoy state have the same i-photon transmittance, which verifies the rationality of the assumption that signal state and decoy state are indistinguishable, and also verifies the security of decoy-state method. In addition,by comparing the secure key rate of two cases including only signal state and signal state + one decoy state before and after photon number splitting attack, we find the former is successful and the latter is failed. This just proves the necessity of the existence of decoy state, verifies that the decoy-state method can indeed resist photon number splitting attack, and further verifies the security of decoy-state method.