Fortify Your Cyber Fortress: Conquer the 2025 NDE Practice Exam! 🚀🔐

The role of a firewall in network security primarily revolves around filtering incoming and outgoing traffic. A firewall acts as a barrier or gatekeeper between a trusted internal network and untrusted external networks, such as the internet. It evaluates the data packets that are trying to enter or leave the network based on a set of predetermined security rules. By doing so, it allows or denies traffic based on the established policies, ensuring that only authorized communication is permitted while blocking potentially harmful data, thereby protecting the network from various threats, including unauthorized access and attacks.

The other functions mentioned, while important in the realm of cybersecurity, do not accurately describe the primary role of a firewall. Firewalls do not inherently encrypt data in transit, as that function is typically handled by protocols designed for encryption, like SSL/TLS. Additionally, while a firewall may monitor network traffic to some extent (giving it visibility into the data being transmitted), its main job is to actively filter that traffic. Lastly, firewalls do not store backup data; that function falls under the domain of backup solutions or storage systems. Therefore, the correct understanding of a firewall's primary function highlights its critical role in network security as a traffic filtering device.