Deck 5: Ethernet 802.3switched Lans

Question 1

Physical layer standards govern ________.

A) signaling
B) physical connectors
C) both A and B
D) neither A nor B

Answer 1

C

Question 2

________ links connect users to workgroup switches.

A) Trunk
B) Core
C) Access
D) Workgroup

Answer 2

C

Question 3

What type of switch connects switches to other switches?

A) trunk switches
B) core switches
C) workgroup switches
D) none of the above

Answer 3

B

Question 4

Ethernet standards are specified at the ________ layer.

A) physical
B) data link
C) both A and B
D) neither A nor B

Question 5

Ethernet messages are ________.

A) frames
B) packets
C) segments
D) not named

Question 6

Ethernet addresses were formerly called ________ addresses.

A) MAC
B) EUI-48
C) both A and B
D) neither A nor B

Question 7

Physical layer standards govern ________.

A) signaling
B) frames
C) packets
D) all of the above

Question 8

________ is the official name for Ethernet addresses.

A) MAC
B) EUI-48
C) both A and B
D) neither A nor B

Question 9

Ethernet forwarding devices are ________.

A) switches
B) routers
C) access points
D) both A and B

Question 10

Ethernet standards are specified at the ________ layer.

A) physical
B) Internet
C) both A and B
D) neither A nor B

Question 11

Ethernet standards are specified at the ________ layer.

A) Internet
B) transport
C) both A and B
D) neither A nor B

Question 12

What 802 Working Group creates Ethernet standards?

A) 802.1
B) 802.2
C) 802.3
D) 802.11

Question 13

Trunk links connect switches to ________ switches.

A) core
B) workgroup
C) both A and B
D) neither A nor B

Question 14

________ links connect switches to other switches.

A) Trunk
B) Long
C) Access
D) Workgroup

Question 15

The path a message takes from the source host to the destination device in an Ethernet network is a ________.

A) physical link
B) data link
C) route
D) label-switched route

Question 16

In digital signaling,there is (are)________ state(s).

A) one
B) only two
C) a small number of
D) an infinite number of

Question 17

What organization (most specifically)creates Ethernet standards?

A) IEEE
B) IETF
C) ISO
D) OSI

Question 18

What type of switch connects users to the network?

A) user switches
B) core switches
C) access switches
D) workgroup switches

Question 19

In this book,we use the terms Ethernet and 802.3 interchangeably.

Question 20

A local area network operates ________.

A) on a customer premises
B) between customer premises
C) both A and B
D) neither A nor B

Question 21

Which UTP quality levels can send signals at 10 gigabits per second?

A) category 6
B) category 6A
C) both A and B
D) neither A nor B

Question 22

To transmit five bits per clock cycle,you must have ________ states.

A) 5
B) 16
C) 32
D) none of the above

Question 23

UTP categories rate the ________ of UTP cabling.

A) quality
B) speed
C) quality-of-service performance
D) error performance

Question 24

Signal state is held constant in a clock cycle ________.

A) for energy efficiency
B) to make it easier for the receiver to sample the state
C) to emphasize differences between clock cycles
D) none of the above

Question 25

How long (in milliseconds)is a clock cycle if I transmit 400 Mbps with four states?

A) 0.000005
B) 0.0025
C) 0.005
D) none of the above

Question 26

The 802.11ac Wi-Fi standard uses 256 states.How many bits can it send per clock cycle?

A) 8
B) 16
C) 32
D) none of the above

Question 27

The main benefit of parallel transmission over serial transmission is ________.

A) reliability
B) speed
C) both A and B
D) neither A nor B

Question 28

Four-pair UTP uses ________ connectors.

A) universal
B) binary
C) ST or SC
D) none of the above

Question 29

In 4-pair UTP,what is twisted?

A) individual wires
B) pairs of wires
C) all eight wires
D) none of the above

Question 30

A system with 16 states can transmit ________ bits per clock cycle

A) 3
B) 4
C) 5
D) none of the above

Question 31

To transmit three bits per clock cycle,you must have ________ states.

A) 3
B) 6
C) 8
D) 16

Question 32

In binary signaling,there is (are)________ state(s).

A) one
B) two
C) between three and ten
D) an infinite number of

Question 33

Optical fiber cords use two strands ________.

A) for reliability through redundancy
B) to form a complete electrical loop
C) to double the transmission speed
D) for full-duplex transmission

Question 34

The ability to transmit in two directions simultaneously is ________.

A) parallel communication
B) full-duplex communication
C) both A and B
D) neither A nor B

Question 35

How many wires are there is a UTP Ethernet cord?

A) 1
B) 2
C) 4
D) 8

Question 36

CAT 5e and CAT 6 wiring can carry Ethernet traffic 100 meters up to ________.

A) 10 Mbps
B) 100 Mbps
C) 1 Gbps
D) 10 Gbps

Question 37

What type of copper wiring is widely used in Ethernet?

A) optical fiber
B) 4-pair UTP
C) both A and B
D) neither A nor B

Question 38

What problem limits transmission distance in 4-pair UTP?

A) reflection at the two ends
B) heat conduction
C) radiation
D) none of the above

Question 39

4-pair UTP terminates in a(n)________ connector.

A) USB
B) RJ-45
C) SC
D) standard telephone

Question 40

If you double the number of states,you can transmit ________ more bit(s)per clock cycle.

A) 1
B) 2
C) 4
D) none of the above

Question 41

Optical fiber cords typically have two fiber strands.This is done to allow ________.

A) redundancy
B) total redundancy
C) half-duplex operation
D) full-duplex operation

Question 42

________ fiber is being sold today.

A) OM2
B) OM4
C) both A and B
D) neither A nor B

Question 43

Fiber that has a core diameter of 8.3 microns is ________.

A) multimode fiber
B) single-mode fiber
C) full duplex fiber
D) exceptionally fast

Question 44

Which of the following is used most often in LANs for fiber transmission links?

A) modal bandwidth fiber
B) 1.550 nm fiber
C) single-mode fiber
D) multimode fiber

Question 45

Two switches that are 200 m apart at a speed of 20 Gbps should be connected using ________.

A) 10GBASE-SR
B) 100GBASE-SR
C) 10GBASE-SR with bonding
D) 100GBASE-SR with bonding

Question 46

Modal dispersion limits transmission distance in ________.

A) multimode fiber
B) single-mode fiber
C) both A and B
D) neither A nor B

Question 47

Which of the following is used most often in LANs for fiber transmission links?

A) 850 nm multimode fiber
B) 850 nm single-mode fiber
C) 850 nm multimode-mode fiber
D) 1,550 nm single-mode fiber

Question 48

Which core diameter is used in multimode fiber.

A) 50 microns
B) 8 microns
C) 50 mm
D) 8 mm

Question 49

In optical fiber,light travels through the ________.

A) core
B) cladding
C) both A and B

Question 50

The distance between two corresponding points in adjacent cycles is the ________.

A) frequency
B) wavelength
C) bandwidth
D) span

Question 51

Which UTP quality levels are needed to send signals 100 meters at 10 gigabits per second?

A) category 6
B) category 6A
C) both A and B
D) neither A nor B

Question 52

________ occurs when the light energies of two pulses arrive at the far end at overlapping times.

A) Multimode transmission
B) Modal bandwidth
C) Modal dispersion
D) Modal interference

Question 53

If a physical link can use either 4-pair UTP,multimode fiber,or single-mode fiber,which should I use?

A) 4-pair UTP
B) multimode fiber
C) single-mode fiber
D) none of the above

Question 54

________ describe light entering a fiber's core at different angles.

A) Co-cycle waves
B) Harmonics
C) Divergences
D) Different modes

Question 55

For what specific purpose were the 2.5GBASE-T and 5GBASE-T standards developed?

A) general growth in demand for Ethernet speed
B) serving access points
C) to provide lower-cost service than 10G-BASE-T
D) none of the above

Question 56

850 nm multimode fiber is used in LANs ________.

A) to keep cost low
B) to have the longest transmission distances
C) both A and B
D) neither A nor B

Question 57

Which light wavelength dominates in LANs?

A) 850 nm
B) 1,310 nm
C) 1,550 nm
D) 1 Gbps

Question 58

The strength of a wave is its ________.

A) amplitude
B) frequency
C) wavelength
D) force

Question 59

The longest transmission distances are possible with ________.

A) USB
B) UTP
C) single-mode fiber
D) multimode fiber

Question 60

What is the quality designator for multimode optical fiber?

A) Cat
B) OM
C) both A and B
D) neither A nor B

Question 61

What is binary 1111 in hex?

A) 10
B) 13
C) 14
D) 15

Question 62

What is 9 hex in binary?

A) 1000
B) 1001
C) 1010
D) 1111

Question 63

EUI-48 addresses in expressed in hexadecimal notation if used by ________.

A) switches
B) routers
C) both A and B
D) neither A nor B

Question 64

Ethernet became the dominant LAN technology because of ________.

A) low cost
B) high speed
C) link reliability
D) agility

Question 65

Having only a single possible path between devices ________.

A) reduces switching cost
B) provides reliability
C) reduces errors
D) none of the above.

Question 66

Which of the following letters may appear in EUI-48 addresses?

A) D
B) H
C) both A and B
D) neither A nor B

Question 67

In large Ethernet networks,there can be ________ possible data links between two hosts.

A) 1
B) 2
C) 3
D) many

Question 68

The two tag frames provide information about ________.

A) transmission media
B) the length of Jumbo packets
C) priority
D) all of the above

Question 69

The PAD field is added by the ________ if the frame is too short without it.

A) sender
B) receiver
C) both A and B
D) neither A nor B

Question 70

A switch knows the entire data link between the source and destination hosts.

Question 71

The switch knows the type of device it is forwarding a frame to.

Question 72

If you can span the distance between two switches with either a single optical fiber link or two UTP lengths with an intermediate switch,which should you choose?

A) single optical fiber link
B) two UTP cords with an intermediate switch
C) both are equally attractive
D) neither will work

Question 73

What is binary 0000 in hex?

A) 0
B) 1
C) 15
D) 16

Question 74

In Ethernet,switches are organized in a ________.

A) ring
B) mesh
C) hierarchy
D) any of the above

Question 75

At what layer is the 100BASE-TX standard?

A) physical
B) data link
C) Internet
D) physical and data link

Question 76

UTP and fiber distance limits are for ________.

A) physical links
B) data link
C) Internet routes
D) physical and data link

Question 77

To span the distance between two switches,why is adding an intermediate switch not an attractive choice?

A) latency
B) errors
C) speed restrictions
D) expense

Question 78

To manage their Ethernet networks,companies rely on ________.

A) SNMP
B) HTTP
C) FTTH
D) none of the above

Question 79

What is F hex in binary?

A) 1001
B) 1010
C) 1111
D) none of the above

Question 80

What is binary 0010 in hex?

A) 1
B) 2
C) 3
D) none of the Above