量子密钥分发是安全分发密钥的一种方式，文件包含其密钥率和传输距离的仿真代码，包含各类协议的比较，直接运行即可，非常有用的资料。。。。(Quantum key distribution (QKD) is a way of secure key distribution. The file contains the simulation code of key rate and transmission distance, and the comparison of various protocols. It can be run directly and is very useful information.)