How does MAC filtering improve network security?

• A. It encrypts wireless traffic using WEP.
• B. It blocks access using firewall rules.
• C. It prevents unauthorized access by allowing only devices on a whitelist to connect to the network.
• D. It assigns fixed IP addresses to all devices.

Answer: (C)

MAC filtering works by creating a whitelist of approved hardware addresses. Each network device’s network interface has a unique MAC address, and the router allows connections only from devices whose MACs are on that list. This helps keep unauthorized devices from associating to the wireless network, since anything not on the list is blocked before data exchange starts.

However, this method isn’t very strong on its own. MAC addresses can be spoofed, so an attacker could imitate an allowed device and gain access. It also doesn’t protect the contents of traffic once a device is connected, and it can be impractical in larger or dynamic networks. For stronger security, MAC filtering should be used in combination with robust encryption (like WPA2/WPA3) and proper authentication.