If unauthorized users know anything about the structure of a block of your plain text, they can use that information to decipher the known cipher text block and possibly recover your key.

如果未经授权的用户知道了您的纯文本块结构的任何信息，他们就可以利用该信息来解密已知的密码文本块，并有可能重新获得您的密钥。

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In the past, Tang had repeatedly denied the existence of the unauthorized structure.

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Infrared cameras and other technology monitor for unauthorized activity in sensitive areas of the structure, including doors to equipment chambers.

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