What role do firewalls play in network security?

Firewalls are a crucial component of network security as they act as a barrier between a trusted internal network and untrusted external networks, such as the internet. Their primary role is to block or permit traffic based on pre-defined security rules. This means that firewalls can analyze incoming and outgoing traffic and determine whether to allow or deny that traffic based on various criteria, including IP addresses, ports, and protocols. By managing this flow of data, firewalls help prevent unauthorized access to sensitive information and mitigate potential threats, such as malicious attacks or data breaches.

While other options may relate to aspects of cybersecurity, they do not describe the primary function of firewalls. For instance, encrypting user data is typically handled by encryption protocols rather than firewalls. Monitoring employee behavior is more associated with user activity monitoring tools or DLP solutions. Providing user authentication is generally carried out by authentication mechanisms and identity management systems, which are distinct from the functionality of a firewall.