The available configuration options for file protection allow for a dizzying array of choices. The CERN web site contains details of the various options. This page will contain more of an introduction with simple examples to allow you to get a feel for the various components and how they inter-relate.
In this tutorial we'll use the phrase "directory" to mean "directory tree starting at the specified base". Thus, the directory /mott also means all sub-directories of /mott . Since there different levels of complexity for protection we'll have separate tutorials for the different components. The complexity will increase with each tutorial, so you should read each in turn.