Address Learning

The switch has a MAC address table, either when the switch receives a data frame , it records the first data frame of the source port mapping and the source MAC address, if the map entry already exists in the MAC address table, the update map survival, if not then save the map entry in the MAC address table. And determining whether the data frame belongs to unicast frame or the broadcast frame, if the broadcast frame (except the port receiving the data frame outer) forwards the data frame to all ports, if the frame is a unicast MAC address lookup table has, in accordance with corresponding map exists for the data transfer according to the MAC address mapping table entry; if not mapped, then the switch broadcasts the frame to be back to the recipient with a corresponding message, it will remember the map corresponding to the MAC address and port, so that the next forwarding, initial learning is thus come