1. What is carrier sense multiple access collision detect (CSMA/CD)?
CSMA/CD describes the Ethernet access method. In CSMA/CD, many stations can
transmit on the same cable, and no station has priority over any other. Before a
station transmits, it listens on the wire to make sure no other station is transmitting.
If no other station is transmitting, the station transmits across the wire. CSMA/CD is
all about devices taking turns using the wire.
2. What are MAC addresses?
For computers to identify each other on the data link layer, they need a MAC address
(hardware address). All devices on a LAN must have a unique MAC address. A MAC
address is a 48-bit (six octet) address burned into a network interface card. The first
three octets (24 bits) of the MAC address indicate the vendor that manufactured the
card. This is called the Organization Unique Identifier (OUI). The last three octets of
the MAC address are the unique host address. An example of a MAC address is 00-
80-C6-E7-9C-EF.
3.What are the three types of LAN traffic?
The three types of LAN traffic are:
Unicasts
Broadcasts
Multicasts
4.What are unicast frames?
Unicast frames are the most common type of LAN traffic. A unicast frame is a frame
intended for only one host. In unicast frames, the only station that processes the
frame is the station that has its own MAC address in the destination portion of the
packet.
5.What are broadcast frames?
Broadcast frames are frames intended for everyone. Stations view broadcast frames
as public service announcements. All stations receive and process broadcast frames.
In large networks, broadcasts can bring the network to a crawl, because every
computer must process them.
6.What is the destination address of broadcast frames?
The destination address of broadcast frames (Layer 2 broadcast addresses) is FF-FF-
FF-FF-FF-FF, or all 1s in binary.
7.What are multicast frames?
Multicast frames address a group of devices that have a common interest. These
frames allow the