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

An access control list (ACL) functions by specifying which users or systems are granted access to specific objects or resources within a network. This mechanism is crucial in managing permissions and ensuring that only authorized individuals or systems can access sensitive data or perform actions on network devices. ACLs can be implemented in various ways, such as at the router or firewall level, controlling traffic flow based on defined rules that grant or deny access based on IP addresses, protocols, or port numbers.

By managing access rights, ACLs help to enforce security policies, minimize the risk of unauthorized access, and mitigate potential vulnerabilities within the network. This makes them a fundamental component of network security.

The other options do not accurately represent the primary function of an ACL. Monitoring network traffic and identifying suspicious activity pertains to intrusion detection systems and network monitoring tools, while defining encryption types refers to mechanisms that secure data in transit. Additionally, recording login attempts is part of logging and auditing systems, which track access for security compliance but are not the main purpose of an ACL.