Packet Fowarding

Question 1

What does CSMA/CD stand for, and what does it do?

Answer 1

Carrier Sense Multiple Access/Collision Detection
It is an Ethernet Protocol used to ensure that only one device talks at a time in a collision domak

Question 2

What is unknown unicast flooding?

Answer 2

A switch will forward/broadcast a packet out all ports when it receives an unknown destination MAC address in order determine where to send the packet too

Question 3

What is broadcast traffic?

Answer 3

Network traffic that is intended for all hosts within the LAN and is forwarded out every switch port

Question 4

What are the 4 802.1Q fields in a packet?

Answer 4

TPID (Tag Protocol Identifier): 16-bit field to identify 802.1Q packet
PCP (Priority Code Point): 3-bit field used to identify a class of service (CoS) as part of layer 2 QoS between switches
DEI (Drop Eligble Indicator): 1-bit field indicates whether a packet can be dropped or not during bandwidth contention
VLAN Identifier: 12-bit field that specifies the VLAN associated with a packet

Question 5

What happens to a packet when it is received on a remote trunk link?

Answer 5

The 802.1Q headers are removed, and the packet is forwarded to the next port, based on the MAC address for that VLAN

Question 6

Where does the MAC address table reside?

Answer 6

In the CAM (content addressable memory), the CAM uses high-speed memory that is faster than typical computer RAM due to its search techniques.