What is a firewall used for in networking?

A firewall serves as a crucial component in network security, functioning primarily to monitor and control incoming and outgoing network traffic based on predetermined security rules. This process involves establishing a barrier between a trusted internal network and untrusted external networks, such as the internet. By analyzing traffic and applying security rules, a firewall can block unauthorized access, prevent malicious activities, and protect sensitive data.

Firewalls can be implemented in hardware, software, or a combination of both, allowing organizations to customize their security setups according to specific needs. This active management of data flow helps ensure that only legitimate traffic is allowed through while malpractices are effectively curtailed, making it an essential tool for maintaining the security and integrity of networked systems.

It’s important to note that while other options may relate to networking, they do not accurately reflect the primary role of a firewall. Enhancing internet speed is not a function of a firewall; it is primarily focused on security. Connecting multiple network segments pertains to routers or switches, rather than firewalls. Storing data temporarily relates to caching or buffering techniques, which fall outside the scope of firewall functionalities.