How Does the Switch Build the CAM Table?

The switch uses a two step process:

Step 1. Learn – Examines Source Address

• Adds the source MAC if not in table
• Resets the time out setting back to 5 minutes if source is in the table

Step 2. Forward – Examines Destination Address

• If the destination MAC is in the MAC address table it is forwarded out the specified port
• If a destination MAC is not in the table, it is flooded out all interfaces except the one it was received