Closed private certificate issuing systems.

封闭私有证书发布系统。

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Open public certificate issuing systems.

开放式公共证书发布系统。

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Trusted certificate authorities issue digital certificates, which are then used to authenticate users and organizations for access to Web sites, E-mail servers, and other secure systems.

可信的证书权威机构发布数字证书，它们被用来鉴别用户和组织访问Web站点，e - mail服务器和其他安全系统的权限。

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Encourage and develop better authentication systems, including PKI (public key infrastructure) and CA (certificate authority) schemes.

CNN: Global panel issues Internet security recommendations

Certificate attacks will be with us as long as MD5 based certificates are used to authenticate critical systems.

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