Which term describes a port security feature that automatically learns and saves the MAC address of the first device connected to a port?

Which term describes a port security feature that automatically learns and saves the MAC address of the first device connected to a port?

• A. Port Security
• B. BPDU Guard
• C. Sticky MAC
• D. Router on a Stick

Answer: (C)

This describes sticky MAC. When port security is configured with sticky learning, the switch dynamically learns the MAC address of the first device that connects to the port and converts that address into a sticky entry that is saved in the switch’s configuration. That locks the port to that single MAC address, blocking other devices from using the port unless the sticky entry is changed. The learned address can also be written to startup-config so the restriction persists after a reboot. This specifically distinguishes it from general port security, which may rely on static or non-persistent dynamic entries, and from BPDU Guard or Router on a Stick, which relate to different features entirely.

This describes sticky MAC. When port security is configured with sticky learning, the switch dynamically learns the MAC address of the first device that connects to the port and converts that address into a sticky entry that is saved in the switch’s configuration. That locks the port to that single MAC address, blocking other devices from using the port unless the sticky entry is changed. The learned address can also be written to startup-config so the restriction persists after a reboot. This specifically distinguishes it from general port security, which may rely on static or non-persistent dynamic entries, and from BPDU Guard or Router on a Stick, which relate to different features entirely.