What is the main purpose of an access control list (ACL) in network security?

An access control list (ACL) serves a critical role in network security by defining permissions for resource access. This allows administrators to control who can access specific resources on a network, thereby enhancing security by ensuring that only authorized users have permission to interact with sensitive data and systems. ACLs can be implemented on various devices, such as routers, firewalls, and servers, and specify both the type of access (such as read, write, or execute) and the users or groups to whom these permissions apply.

By effectively managing permissions through ACLs, organizations can help protect their assets from unauthorized access and potential security threats, making it a foundational component in safeguarding network resources. This control mechanism is essential for enforcing security policies and ensuring compliance with regulations that require data protection.