How do switches and bridges learn where the devices are located on a network?

How do switches and bridges learn where the devices are located on a network?

How do switches and bridges learn where the devices are located on a network?




  1. When a frame enters a port, the source MAC address is copied from the frame header.
  2. Bridges and switches learn addresses by copying the MAC address of the source device and placing it into the MAC address table. The port number which the frame entered is also recorded in the table and associated with the source MAC address.
  3. The switch or the bridge cannot record the destination MAC address because it does not know the port that is used to reach the destination device. Bridges and switches operate at Layer 2 and do not use IP addresses (which exist at Layer 3).