该文分析了窃听者采用不同测量基对经典BB84量子密钥分发协议进行测量重发攻击所能获得的信息量以及在接收端造成的比特错误概率,得到合法用户判断是否存在窃听重发攻击的比特错误率上限低于15%,从而为合法通信者间的安全通信和对窃听者的检测提供了新的判定依据。
The amount of information and the bit error rate caused by eavesdropper are analyzed while the BB84 quantum key distribution protocol is attacked with intercept/resend attack using different measurement bases.The bit error rate threshold that legitimate user used to determine intercept/resend eavesdropping attack is under 15%,and a new standard is provided for secure quantum communications and the detection of eavesdropper.