What is the purpose of a firewall in networking?

The purpose of a firewall in networking is primarily to protect networks by filtering incoming and outgoing traffic. Firewalls act as a barrier between trusted internal networks and untrusted external networks (like the internet), inspecting data packets to determine whether they should be allowed through or blocked based on predetermined security rules. This helps prevent unauthorized access, cyber attacks, and the spread of malware, thereby safeguarding sensitive information and ensuring the overall integrity of the network.

The other options do not accurately reflect the main function of a firewall. Providing a physical separation between devices is more related to physical security and network architecture rather than the operation of a firewall. Managing bandwidth allocation refers to the optimization of the use of network resources, which is not a role fulfilled by a firewall. Enhancing wireless connectivity pertains to improving signal strength and coverage, which is unrelated to the security features that a firewall offers.