youdao

This design presents a reasonably secure system; as long as each voting user has one and only one acceptable E-mail account, there is reasonable assurance that users could not vote twice.

这种设计可以得到一个比较安全的系统；条件是每个投票的用户都有且只有一个可以接受的电子邮件帐号，这样就可以保证每个用户都不会投两次票。

youdao

The solution, which makes use of the method of combining PKI with S/MIME, establishes a system of secure E-mail transfer, according to the application principle of Public Key Infrastructure(PKI).

该方案依据PKI（公钥基础设施）的应用原理，采用PKI与S MIME相结合的方法，建立了基于PKI的安全邮件传输体系。

youdao

"We urgently need to start reinforcing the system that is currently used to authenticate and identify secure websites and e-mail systems, " said Mr Eckersley.

BBC: Iran accused in 'dire' net security attack