加密算法通过在消息上执行一连串的数学操作从而对消息进行加密或解密，转换的是消息的外观而非其内容。

Encryption algorithms encrypt or decrypt messages by performing a sequence of mathematical operations on the message, transforming its appearance but not its content.

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有操作模式，例如AES-CBC和不安全的AES-ECB，它们需要填充，因为它们也对每个块进行加密/解密。

There are modes of operation such as AES-CBC and the insecure AES-ECB that do require padding, as they encrypt/decrypt per block as well.

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该系统能有效的防止网络内部的重要数据通过网络泄露出去，无需用户进行手动的加密解密操作。

The system can effectively prevent important data from leaking out through the network without manual encryption and decryption operations.

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