What is the purpose of a firewall policy?

A firewall policy serves a critical role in network security by defining access rules for traffic. It establishes what types of network traffic are allowed or denied based on specified criteria such as source and destination IP addresses, protocols, and ports. By implementing these rules, a firewall policy protects network assets from unauthorized access and potential threats, ensuring that only legitimate traffic can flow through.

The other options, while important in the broader context of network management and security, do not directly pertain to the primary function of a firewall policy. For instance, encrypting sensitive data involves protecting data in transit or at rest, which is a separate function typically handled by encryption protocols rather than firewall policies. Monitoring network performance focuses on assessing the efficiency and responsiveness of the network, generally falling under the domain of network management tools. Providing device configuration pertains to the settings and parameters needed for the operation of network devices, which is also outside the defining scope of a firewall policy.