The NSA found that most operating systems' security mechanisms, including Windows and most UNIX and Linux systems, only implement "discretionary access control" (DAC) mechanisms.

NSA发现大部分操作系统的安全机制，包括Windows和大部分UNIX和Linux系统，只实现了“选择性访问控制(discretionary access control)”(DAC)机制。

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To address the problem, Hyatt implemented mobile-device management systems that allow it to deal with multiple operating systems more smoothly and address security, monitoring and technical-support issues more efficiently.

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He spent 12 years at Sun Microsystems as a distinguished engineer where he worked on areas such as networking, security, and operating systems.

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However, I have a feeling that we really ought to be paying more attention to the security of our other operating systems now.

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