What is the main function of network firewalls?

The main function of network firewalls is to protect networks by filtering traffic. In essence, firewalls serve as a barrier between trusted internal networks and untrusted external networks, such as the internet. They inspect incoming and outgoing traffic based on predetermined security rules to determine which packets of data should be allowed to pass through and which should be blocked. This filtering process is crucial for preventing unauthorized access to sensitive information and for blocking malicious traffic that could potentially exploit vulnerabilities within the network.

Firewalls can be configured to allow or deny traffic based on various criteria, including IP addresses, port numbers, and protocols. By managing these traffic rules, firewalls help maintain the confidentiality, integrity, and availability of data within a network, effectively reducing the risk of cyber threats.

While other options may reflect functions related to network security, they do not capture the primary role of firewalls. For instance, analyzing data packets might be a part of what a firewall does, but it is not its main function. Similarly, while firewalls can contribute to network performance, they are not designed to increase internet speeds. Lastly, although some firewalls may also include intrusion detection capabilities, detection itself is not the fundamental purpose of a firewall. Thus, the function of filtering traffic remains the core