What is the primary role of a Firewall in networking?

The primary role of a firewall in networking is to control the flow of network traffic. Firewalls act as a barrier between trusted internal networks and untrusted external networks, such as the internet. They monitor and filter incoming and outgoing traffic based on predefined security rules. This control helps protect an organization's network by allowing only authorized traffic to pass while blocking potentially harmful data packets. By determining which traffic is permitted or denied, firewalls help maintain the security and integrity of the network, reducing the risk of unauthorized access or cyberattacks.

While other options represent important functions in a network environment, they do not define the primary purpose of a firewall. Encrypting data in transit is primarily the function of VPNs or encryption protocols, physically separating network segments usually requires devices such as routers or switches, and performing regular backups of network data is a function of backup solutions and data management systems rather than firewalls.