200-301: Cisco Certified Network AssociateDemo

By Cisco · Question Mode

QuestionQ227

Network Fundamentals

How is MAC learning performed on a switch?

  • A protects against denial of service attacks
  • B sends frames with unknown destinations to a multicast group
  • C adds unknown source MAC addresses to the address table
  • D sends a retransmission request when a new frame is received
Explanation

A switch learns Layer 2 reachability by inspecting the source MAC address of each incoming frame and associating that address with the port on which the frame was received in its MAC address table. This learned mapping is then used to make forwarding decisions for future frames destined for that MAC address.

Learn more

Community Discussion

No comments yet. Be the first to start the discussion!