Building the MAC address table

Lets say a MAC address cannot be found in the MAC address table of frame addressed as a broadcast. Then the switch acts like a hub and transmits the frame out of all the ports. The switch will build the MAC address table by analyzing incoming frames for a source of MAC address. It can then also add MAC address entry against the particular port number. Entries remain in the MAC address table for a period before being flushed from the table.This will ensure that problems with the switch are not encountered when MAC addresses or network cards are changed.