The public key infrastructure (PKI) is the foundation and center of network security architecture now, can provide security services including confidentiality, authentication, dig2ital signatures and integrity.

PKI(public key infrastructure) and CA(certificate authority)

随着社会的发展以及企业的不断壮大，企业网的范围也不断扩大，从一个本地网络发展到跨地区跨城市甚至是跨国家的网络。随着各种网络应用不断涌现，在采用网络应用较多的企业中，出现了安全管理和安全通讯的问题，近年来开始越来越多应用到企业、行业中的，是一种通用的PKI(public key infrastructure)安全体系，其运营管理机构一般又称为CA证书机构。

A Public Key Infrastructure (PKI) binds cryptographic public keys to physical entities through digital certificates. A PKI includes components that issue digital certificates and distribute certificate status information. PKI users select one or