What is the primary purpose of an access control list (ACL)?

The primary purpose of an access control list (ACL) is to serve as a collection of access control entries (ACEs) associated with a file or folder. Each ACE specifies the permissions that a user or group has regarding that particular resource. This is crucial for managing and enforcing security policies within a system by determining who can access, modify, or execute a file or folder based on their assigned permissions.

The mechanics of an ACL allow for granular control over access rights, enabling administrators to define precise rules about who can do what with a specific resource. This plays a vital role in maintaining the integrity and security of data, as it restricts access to authorized users only, thereby helping mitigate the risk of unauthorized actions or breaches.

Other options refer to different aspects of information security. Encryption is a separate process aimed at protecting data confidentiality; monitoring network traffic deals with intrusion detection and prevention rather than local access control; and data backup is related to recovery processes, which don't directly address the access permissions for files or folders. Thus, while those processes are important for comprehensive security strategies, they do not fulfill the essential function that an ACL performs.