As packets travel from Mary to Robert, which three devices will use the destination MAC address
of the packet to determine a forwarding path? (Choose three.)
A.
Hub1
B.
Switch1
C.
Router1
D.
Switch2
E.
Router2
F.
Switch3
Explanation:
Switches use the destination MAC address information for forwarding traffic, while routers use the
destination IP address information.
Local Area Networks employ Layer 2 Switches and Bridges to forward and filter network traffic.
Switches and Bridges operate at the Data Link Layer of the Open System Interconnect Model
(OSI). Since Switches and Bridges operate at the Layer 2 they operate more intelligently than
hubs, which work at Layer 1 (Physical Layer) of the OSI. Because the switches and bridges are
able to listen to the traffic on the wire to examine the source and destination MAC address. Being
able to listen to the traffic also allows the switches and bridges to compile a MAC address table to
better filter and forward network traffic.
To accomplish the above functions switches and bridges carry out the following tasks:
MAC address learning by a switch or a bridge is accomplished by the same method. The switch orbridge listens to each device connected to each of its ports and scan the incoming frame for the
source MAC address. This creates a MAC address to port map that is cataloged in the
switches/bridge MAC database. Another name for the MAC address table is content addressable
memory orCAM table.
When a switch or bridge is listening o the network traffic, it receives each frame and compares it to
the MAC address table. By checking the MAC table the switch/ bridge are able o determine which
port the frame came in on. If the frame is on the MAC table the frame is filtered or transmitted on
only that port. If the switch determines that the frame is not on the MAC table, the frame is
forwarded out to all ports except the incoming port.