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简述 VPN的工作原理。

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答:是在 IP 通信网络上, 利用传统设备对于发出和接收的 IP 包进行加解密, 在通信的两端之间建立密文通信信道。两个 VPN设备之间的通信可以是在公共网络或者 Internet 上完成的,但却可以获得像是在一个私有网络内通信的高安全性。

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