What function does a firewall perform in network security?

A firewall serves as a protective barrier in network security by controlling incoming and outgoing network traffic based on predetermined security rules. Its primary function is to establish a set of protocols to permit or block data packets, which helps prevent unauthorized access to or from a private network. By doing so, it safeguards sensitive information from potential threats, such as hackers or malware.

This essential role in securing networks distinguishes firewalls from other types of software. For instance, while a mechanism for accelerating data transfer speed focuses on improving the performance of data transmission, it does not provide any security features. Similarly, an application for managing hardware resources deals with optimizing the use of a computer's components, and tools for improving user interface design are aimed at enhancing the user experience rather than protecting data integrity. This clarity on the specific function of a firewall helps highlight its crucial role in network security.