Module 7: The Access Layer
Ethernet switches make their forwarding decision based on what field of the Ethernet frame?
Destination MAC address
When a switch receives an Ethernet frame and the destination MAC address of that frame is not in its MAC address table, the switch will:
Forward the frame out all ports except in the incoming port
Which statement is correct about Ethernet switch frame forwarding decisions?
Frame forwarding decisions are based on MAC address and port mappings in the MAC Address table
What will a Layer 2 switch do when the destination MAC address of a received frame is not in the MAC table?
It forwards the frame out of all ports except for the port at which the frame was received.
What will a host on an Ethernet network do if it receives a frame with a unicast destination MAC address that does not match its own MAC address?
It will discard the frame
The Ethernet protocol is at what layer of the OSI Model?
Layer 2 Data Link
Which Ethernet frame field indicates the beginning of an Ethernet frame?
Preamble and SFD
Ethernet switches add entries to their MAC address table based on what field of the Ethernet frame?
Source MAC address
When an Ethernet frame is sent out an interface, the destination MAC address indicates:
The MAC address of the device, which is on this network, that will receive the Ethernet frame
Refer to the exhibit. The exhibit shows a small switched network and the contents of the MAC address table of the switch. PC1 has sent a frame addressed to PC3. What will the switch do with the frame?
The switch will forward the frame to all ports except port 4
What is one function of a Layer 2 switch?
determines which interface is used to forward a frame based on the destination MAC address
The process of prepending protocol information with information from another protocol is called:
encapsulation
What process is used to place one message inside another message for transfer from the source to the destination?
encapsulation
Ethernet hubs are considered:
obsolete
Which three fields are found in an 802.3 Ethernet frame?
source physical address, frame check sequence, destination physical address
Which network device has the primary function to send data to a specific destination based on the information found in the MAC address table?
switch
What addressing information is recorded by a switch to build its MAC address table?
the source Layer 2 address of incoming frames
Which information does a switch use to keep the MAC address table information current?
the source MAC address and the incoming port
What is the purpose of the FCS field in a frame?
to determine if errors occurred in the transmission and reception
