To apply theory of cryptology to solve information security effectively,a system have been designed to bind public key and entity info,that is PKI(Public Key Infrastructure).

• 为了将密码学的理论投入实际应用之中并有效地解决安全问题,人们设计了一种机制来解决公钥与实体身份之间的绑定问题,这就是PKI(即公共密钥基础设施)。