6.8 Summary

The Unix filesystem is the primary tool that is used by the Unix operating system for enforcing computer security. Although the filesystem's concepts of security—separate access permissions for the file's user, group, and world—are easy to understand, a Unix system can be very difficult to administer because of the complexity of getting every single file permission correct.

Because of the attention to detail required by the Unix system, you should use measures beyond the filesystem to protect your data. One of the best techniques that you can use is encryption, which we describe in the next chapter.