What is the primary role of firewalls in network security?

The primary role of firewalls in network security is to monitor and control incoming and outgoing network traffic based on predetermined security rules. This function is crucial because firewalls act as a barrier between a trusted internal network and untrusted external networks, such as the internet. By establishing a set of rules, firewalls determine which traffic should be allowed to pass through and which should be blocked, thus helping to prevent unauthorized access and attacks on the network.

This ability to filter traffic based on security policies is essential for protecting sensitive data and maintaining the integrity of the network. Firewalls can be configured to recognize and respond to various types of threats, including malware, unauthorized access attempts, and other vulnerabilities. This proactive monitoring is a fundamental aspect of maintaining network security.

The other options do not align with the primary function of firewalls. Establishing a connection between different networks is typically the role of routers, while providing backup for network data is a function of backup systems or services. Enhancing wireless signal strength is related to networking equipment like access points and not to the security functions of firewalls.