Allied Telesis AT-FS705LE - Manual (Page 22)

Overview
10
The switch also checks the destination MAC
address of each frame it receives. The
destination address is the MAC address of the
end-node to which the frame is intended. If the
address is in the table, the switch directs the
frame directly to the port where the end-node is
located. This helps to ensure that end-nodes
will only receive traffic that is intended for
them and not have to deal with traffic intended
for other end-nodes.
If the destination address is not in the MAC
address table, the switch broadcasts the frame
to all switch ports. When the destination end-
node responds, the switch will be able to match
the address to a port so that the next time a
frame is destined to that particular end-node,
the switch will be able to forward the frame to
the correct port instead of having to broadcast
the frame to all ports.
In some cases a switch will even discard a
frame. If the switch receives a frame that is
destined to an end-node on the same port on
which the frame was received, the switch
discards the frame.
The MAC address table in the AT-FS705LE
switch can store up to 2,000 MAC addresses. To
prevent the table from becoming filled with
addresses of end-nodes that are no longer
active, the switch has a MAC address aging
timer. This timer will delete a MAC address