7-1-3 Permissions and Access Rights Explained

Key Concepts

• Permissions
• Access Rights
• User Roles
• File and Directory Permissions
• Inheritance
• ACLs (Access Control Lists)

Permissions

Permissions define the actions that can be performed on a resource, such as a file or directory. Common permissions include read, write, and execute. Read permission allows viewing the content, write permission allows modifying the content, and execute permission allows running the file as a program.

Access Rights

Access rights are the specific permissions granted to a user or group for a particular resource. These rights determine what actions the user or group can perform on the resource. Access rights are crucial for maintaining security and controlling who can access sensitive information.

User Roles

User roles are predefined sets of permissions assigned to users based on their job functions or responsibilities. Common roles include administrator, editor, and viewer. Each role has a specific set of access rights that determine what actions the user can perform.

File and Directory Permissions

File and directory permissions are the specific access rights assigned to files and directories. These permissions can be set for the owner, group, and others. For example, a file might have read and write permissions for the owner, read-only permissions for the group, and no permissions for others.

Inheritance

Inheritance is a mechanism where permissions set on a parent directory are automatically applied to its subdirectories and files. This simplifies permission management by allowing administrators to set permissions once at a higher level and have them propagate down the directory tree.

ACLs (Access Control Lists)

ACLs are a more granular way of managing permissions. Unlike traditional permissions that apply to the owner, group, and others, ACLs allow specifying permissions for individual users or groups. This provides more flexibility and control over access rights.

Examples and Analogies

Think of permissions as keys to a locked room. Read permission is like having a key to open the door and look inside, write permission is like having a key to change the contents inside, and execute permission is like having a key to operate a machine inside the room.

Access rights are like a security badge that grants access to certain areas of a building. The badge determines which doors you can open and what you can do in those areas.

User roles are like job titles in a company. An administrator is like the CEO who has access to everything, an editor is like a manager who can make changes, and a viewer is like an employee who can only look at the information.

File and directory permissions are like locks on individual rooms and hallways in a building. Each lock has different keys for the owner, group, and others.

Inheritance is like setting a rule for a floor in a building. If you set a rule that everyone on the floor can access a certain room, all the rooms on that floor will follow the same rule unless you specify otherwise.

ACLs are like having a personalized key for each person. Instead of a generic key that fits everyone, each person has a unique key that grants them specific access rights.