If a switch receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF, what action does the switch take?

If a switch receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF, what action does the switch take?

• A. The switch refreshes the timer on that entry.
• B. The switch does not forward the frame.
• C. The switch sends the frame to a connected router because the destination MAC address is not local.
• D. The switch forwards it out all ports except the ingress port.

Answer: (D)

Broadcast traffic uses the all-ones MAC address, so a switch treats it as intended for every device on the local network segment. To reach every host, the switch floods the frame out all ports in the same VLAN except the port where the frame arrived. This ensures every device can see the broadcast without needing a specific destination mapping. So the frame isn’t sent to a single host, and it isn’t dropped or sent to a router by default. The switch does acknowledge the frame by forwarding it to all other accessible ports, which is exactly why the correct behavior is to forward to all ports except the ingress port.

Broadcast traffic uses the all-ones MAC address, so a switch treats it as intended for every device on the local network segment. To reach every host, the switch floods the frame out all ports in the same VLAN except the port where the frame arrived. This ensures every device can see the broadcast without needing a specific destination mapping.

So the frame isn’t sent to a single host, and it isn’t dropped or sent to a router by default. The switch does acknowledge the frame by forwarding it to all other accessible ports, which is exactly why the correct behavior is to forward to all ports except the ingress port.