What is the main function of a firewall rule?

The primary function of a firewall rule is to determine which types of traffic are allowed or denied through the firewall. Firewalls use these rules to filter incoming and outgoing network traffic based on predetermined security criteria. This means that it can block unwanted traffic that may pose a threat while allowing legitimate traffic to pass through.

Understanding firewall rules is crucial for maintaining network security, as they are fundamental in establishing a boundary between trusted internal networks and potentially untrusted external networks. By defining these parameters, organizations can protect their resources from unauthorized access and various cyber threats, while ensuring that essential communications remain functional.

Other options, while relating to network security, serve different purposes. For example, encrypting data is vital for protecting information during transmission, antivirus protection focuses on detecting and responding to malware, and monitoring user activity is essential for tracking behaviors and identifying anomalies in network usage. However, none of these functions are the primary role of a firewall rule specifically.