A Layer 2 switch maintains a MAC address table to map MAC addresses to their corresponding egress ports. When SW1 receives a frame from PC1 on port GE1/0/2, it inspects the source MAC address. SW1 finds an existing entry for PC1's MAC address associated with port GE1/0/1. Because the frame arrived on a different port (GE1/0/2), the switch concludes that the device has moved. It updates the MAC address table by overwriting the old entry, associating PC1's MAC address with the new port, GE1/0/2. This ensures future frames destined for PC1 are correctly forwarded to its new location.

A: A switch's MAC address table cannot have two different port entries for the same unicast MAC address. This would create forwarding ambiguity.

C: A single MAC address move does not trigger a flush of the entire MAC address table. This would be inefficient and cause unnecessary flooding for all other traffic.

D: Waiting for the original entry to age out would cause a temporary loss of connectivity for PC1, as frames would be forwarded to the old, disconnected port. Switches are designed to update MAC entries immediately to support device mobility.

1. Huawei HCIA-Datacom V1.0 Training Material

"Ethernet Switching Principles

" Section: MAC Address Table Operation. This section describes the process of dynamic MAC address learning

including how a switch updates an entry when a device moves from one port to another.

2. Computer Networking: A Top-Down Approach

8th Edition by J. Kurose and K. Ross

Chapter 6

"The Link Layer and LANs." The section on Link-Layer Switches explains the self-learning process

including how switch tables are updated when a host moves to a different port on the same switch.