1. The switch establishes the mapping of the address with the AC port according to the source MAC address in the received data frame and writes it to the MAC address table.

2. The switch compares the destination MAC address in the data frame with the established MAC address table to determine which port to forward.

3. If the destination MAC address in the data frame is not in the MAC address table, it is forwarded to all ports. This process is called flooding.

4. Broadcast frames and multicast frames are forwarded to all ports.