What is the primary purpose of a firewall?

The primary purpose of a firewall is to monitor and control incoming and outgoing network traffic based on predetermined security rules. This critical function helps establish a barrier between a trusted internal network and untrusted external networks, such as the Internet. By evaluating traffic against defined security policies, a firewall can determine whether to allow or block specific data packets based on criteria like IP addresses, ports, and protocols.

This capability helps protect networked devices from unauthorized access and potential threats, such as malware, intrusions, and data breaches. Firewalls can be implemented through hardware or software solutions, providing flexibility and scalability for different network environments. In essence, they serve as a safeguard to uphold the security and integrity of sensitive data and network resources, ensuring that only legitimate traffic is permitted while harmful traffic is effectively blocked.

The other options highlight different functions that are not the primary role of a firewall, such as enhancing network performance, encrypting data, or providing remote access, which are managed by other security mechanisms or technologies.