Chapter 4

Question 1

(MAC)stands for what. p88

Answer 1

Media Access Control (MAC)

Question 2

(DNS)stands for what. p89

Answer 2

Domain Name Service (DNS)

Question 3

what is Ethernet. p90

Answer 3

is a contention media-access method that allows all hosts on a network to share the same bandwidth of a link.

Question 4

what is a Collision Domain p90

Answer 4

is an Ethernet term that refers to a particular network scenario wherein one device sends a packet out on a network segment, thereby forcing every other device on that same physical network segment to pay attention to it.

Question 5

a situation where each device’s digital signals interfere with another on the wire—occurs and forces the devices to retransmit later. p90

Answer 5

collision event

Question 6

Ethernet uses both Data Link and Physical layer specifications. true or false p90

Answer 6

True

Question 7

what is a Broadcast Domain p90

Answer 7

A broadcast domain refers to the set of all devices on a network segment that hear all the broadcasts sent on that segment.

Question 8

a protocol that helps devices share the bandwidth evenly without having two devices transmit at the same time on the network medium. p91

Answer 8

Carrier Sense Multiple Access with Collision Detection (CSMA/CD)

Question 9

When a collision occurs on an Ethernet LAN, the following happens: p92

Answer 9

A jam signal informs all devices that a collision occurred.
The collision invokes a random backoff algorithm.
Each device on the Ethernet segment stops transmitting for a short time until the timers expire.
All hosts have equal priority to transmit after the timers have expired.

Question 10

And following are the effects of having a CSMA/CD network sustaining heavy collisions: p92

Answer 10

Delay
Low throughput
Congestion

Question 11

Full-duplex Ethernet can be used in many situations; here are some examples: p93

Answer 11

With a connection from a switch to a host
With a connection from a switch to a switch
With a connection from a host to a host using a crossover cable

Question 12

This rate is something known as an __________which translates as “you’re supposed to get” 100 percent efficiency. p93

Answer 12

aggregate rate

Question 13

You can run full duplex with just about any device except a hub. true or false p93

Answer 13

true

Question 14

Ethernet at the Data Link layer is responsible for Ethernet addressing, commonly referred to as what. p94

Answer 14

hardware addressing or MAC addressing

Question 15

are made up of hexadecimal addresses. p94

Answer 15

Ethernet MAC addresses

Question 16

(MAC)stands for what. p98

Answer 16

Media Access Control (MAC)

Question 17

(OUI)stands for what. p98

Answer 17

organizationally unique identifier (OUI)

Question 18

(CRC)stand for what. p99

Answer 18

cyclic redundancy check (CRC)

Question 19

An alternating 1,0 pattern provides a 5MHz clock at the start of each packet, which allows the receiving devices to lock the incoming bit stream. p99

Answer 19

Preamble

Question 20

The preamble is seven octets, and the SFD is one octet (synch). The SFD is 10101011, where the last pair of 1s allows the receiver to come into the alternating 1,0 pattern somewhere in the middle and still sync up and detect the beginning of the data. p99

Answer 20

Start Frame Delimiter (SFD)/Synch

Question 21

This transmits a 48-bit value using the least significant bit (LSB) first. The DA is used by receiving stations to determine whether an incoming packet is addressed to a particular host. The DA can be an individual address or a broadcast or multicast MAC address. Remember that a broadcast is all 1s (or Fs in hex) and is sent to all devices, but a multicast is sent only to a similar subset of hosts on a network. p99

Answer 21

Destination Address (DA)

Question 22

is a 48-bit MAC address used to identify the transmitting device, and it uses the LSB first. p100

Answer 22

Source Address (SA)

Question 23

what is a Length or Type p100

Answer 23

802.3 uses a Length field, but the Ethernet frame uses a Type field to identify the Network layer protocol. 802.3 by itself cannot identify the upper-layer routed protocol and must be used with a proprietary LAN—Internetwork Packet Exchange (IPX)

Question 24

This is a packet sent down to the Data Link layer from the Network layer. The size can vary from 64 to 1500 bytes. p100

Answer 24

Data

Question 25

is a field at the end of the frame that’s used to store the CRC. p100

Answer 25

Frame Check Sequence (FCS)

Question 26

s a computer-networking arrangement where two or more network interfaces on a host are combined for redundancy and/or increased throughput. p101

Answer 26

Channel bonding (also known as Ethernet bonding)

Question 27

Each Ethernet cable type that is specified by the EIA/TIA has something known as. p102

Answer 27

inherent attenuation