Chapter 6 Quiz

6) In a Wi-Fi LAN, wireless hosts generally send frames directly to one another. TRUE OR FALSE

FALSE

63) Within a BSS (and without MU-MIMO), the access point and a wireless host it serves can transmit at the same time. TRUE OR FALSE

FALSE

12) Most wireless systems operate in the ________ range. A) hz B) kHz C) MHz D) GHz

GHz

4) Wi-Fi is a term used by the ________. A) IEEE B) Wi-Fi Alliance C) both A and B D) neither A nor B

Wi-Fi Alliance

76) Individual throughput for users of an access point ________. A) depends on how many users are sharing the access point B) depends on your distance from the access point C) both A and B D) neither A nor B

both A and B

77) As your wireless client travels away from an access point, ________. A) errors begin to increase B) your transmission speed decreases C) both A and B D) neither A nor B

both A and B

80) MIMO ________. A) increases transmission speed B) increases transmission distance C) both A and B D) neither A nor B

both A and B

11) Frequency is measured in terms of ________. A) nanometers B) hertz C) microns D) microseconds

hertz

40) The downside of unlicensed bands is potential ________ A) speed loss B) loss of flexibility C) interference from others D) less-developed standards

interference from others

66) When a receiver transmits an ACK, ________. A) it must use CSMA/CA B) it must use CSMA C) in must use CA D) it must transmit immediately

it must transmit immediately

26) The set of frequencies used for police communication in a city are ________. A) channels B) frequencies C) spectrums D) none of the above

none of the above

28) Wi-Fi operates in the 2.4GHz and 5GHz ________. A) frequencies B) spectrums C) channels D) service bands

service bands

84) If an 802.11n client tries to use an 802.11ac access point, ________. A) they will not be able to communicate B) they will communicate using 802.11n C) they will communicate using 802.11ac D) either B or C

they will communicate using 802.11n

91) The main problem with the 60 GHz unlicensed band is that ________. A) it cannot be used outside B) it does not support MIMO C) transmission speed is low D) transmission distance is short

transmission distance is short

60) If there is an access point that serves eight wireless hosts, on how many channels will these devices transmit and receive during the course of an hour or two? A) 1 B) 2 C) 8 D) 9

1

74) ________ is among the most widely used 802.11 transmission standards used today. A) 802.11g B) 802.11ac C) both A and B D) neither A nor B

802.11ac

75) Today, Wi-Fi sales are dominated by ________. A) 802.11a B) 802.11g C) 802.11n D) 802.11ac

802.11ac

90) Which of the following works in the 60 GHz unlicensed service band? A) 802.11ac B) 802.11ad C) 802.11ax D) all of the above

802.11ad

9) Simple installation rules are sufficient to reduce propagation problems to nonissues in ________. A) 802.3 B) 802.11 C) both A and B D) neither A nor B

802.3

53) A single access point, and the set of hosts it serves, is called a(n) ________. A) BSS B) BSSID C) ESS D) none of the above

BSS

54) In roaming, a wireless client moves from one ________ to another without losing its connection. A) ESS B) BSS C) SSID D) none of the above

BSS

68) Which is one of the only two reliable protocols we have seen this term? A) IP B) CSMA/CA+ACK C) UDP D) 802.3

CSMA/CA+ACK

70) The 802.11 standard has two mechanisms for media access control. Of the two, ________ is mandatory. A) MAC B) CSMA/CA+ACK C) RTS/CTS D) CSMA/CD

CSMA/CA+ACK

71) Which of the following is more efficient and faster? A) CSMA/CA+ACK B) RTS/CTS C) Both are about equally efficient and fast.

CSMA/CA+ACK

87) If two products both comply with 802.11 ac, their performance will always be similar. TRUE OR FALSE

FALSE

83) Which of the following allows access point transmission two wireless clients simultaneously? A) CSMA/CA+ACK B) MIMO C) MU-MIMO D) none of the above

MU-MIMO

82) An access point can transmit to more than one wireless client at a time with ________. A) bonding B) MIMO C) Multiuser MIMO D) CSMC/CA+ACK

Multiuser MIMO

69) In ________, when a wireless host wishes to send, it first sends a message to the wireless access point asking for permission to send. When the access point sends back a response, the host sending the original message may transmit. All other hosts must wait. A) CSMA/CA+ACK B) CSMA/CA C) CSMA/CD D) RTS/CTS

RTS/CTS

56) To use an access point, you need to know its ________. A) SSID B) BSSID C) ESSID D) Wi-Fi ID

SSID

59) To connect to an access point, you must know its ________. A) SSID B) ESSID C) IP address D) Wi-Fi ID

SSID

67) CSMA/CA+ACK is ________. A) unreliable B) reliable C) semireliable

reliable

7) Wireless access points typically link wireless clients to ________. A) wireless servers B) servers on the wired network C) both A and B

servers on the wired network

19) What propagation problem becomes worse when there is a large, and dense, object between sender and receiver? A) multipath interference B) shadow zones (dead zones) C) inverse square law attenuation D) none of the above

shadow zones (dead zones)

65) In CSMA/CD+ACK, when a wireless NIC wishes to transmit, it listens for traffic. If there is traffic, it waits. When the traffic stops, it may transmit immediately. A) always true B) sometimes true C) always false

sometimes true

29) Signals in a transmission usually ________. A) travel at a single frequency B) spread over a range of frequencies C) spread over the entire frequency distribution D) spread over the entire service band

spread over a range of frequencies

21) Multipath interference is mitigated through ________. A) broadband transmission B) MIMO C) beamforming D) spread spectrum transmission

spread spectrum transmission

88) What is the main promise of 802.11ax over 802.11ac? A) higher speed B) the ability to serve more users C) MIMO D) Mu-MIMO

the ability to serve more users

2) ________ is a wireless network standard. A) OSI B) TCP/IP C) both A and B D) neither A nor B

OSI

1) Wireless network standards operate at ________. A) the data link layer B) the Internet layer C) both A and B D) neither A nor B

the data link layer

57) Access points in the same ESS communicate via ________. A) wireless transmission B) the distribution system C) a master access point D) routers

the distribution system

23) The frequency spectrum extends ________. A) into the gigahertz range B) into the visible light range C) into the ultraviolet range D) to infinity

to infinity

78) MIMO ________. A) bonds two or more channels for higher speed B) is used in all forms of 802.11 C) uses a single spatial stream but multiple signals D) transmits multiple signals in the same channel

transmits multiple signals in the same channel

37) Many 802.11 standards work in the 5 GHz_____. A) licensed spectrum B) unlicensed spectrum C) licensed service band D) unlicensed service band

unlicensed service band

72) When does it make sense to use RTS/CTS? A) when all devices can hear each other B) when not all of the devices can hear each other C) when efficiency is crucial D) always

when not all of the devices can hear each other

55) ________ have SSIDs. A) Wireless clients B) Wireless access points C) both A and B D) neither A nor B

wireless access points

8) Compared to wired transmission, propagation problems in radio transmissions are ________. A) worse B) about as bad C) better

worse

39) In unlicensed bands, ________. A) you can use radios wherever you please B) you can prevent nearby businesses from setting up access points in the same channel C) both A and B D) neither A nor B

you can use radios wherever you please

16) If a signal has a strength of 100 mW at 10 meters, how strong will it be at 100 meters? A) about 10 mW B) about 1 mW C) about 0.1 D) none of the above

about 0.1

17) If the signal strength from an omnidirectional radio source is 100 mW at 10 meters, how strong will it be at 30 meters, ignoring absorptive attenuation? A) about 30 mW B) about 11 mW C) about 4 mW D) about 0.1 mW

about 11 mW

15) If a signal has a strength of 100 mW at 10 meters, how strong will it be at 40 meters? A) about 0.5 mW B) about 5 mW C) about 25 mW D) about 6 mW

about 6 mW

18) What propagation problem is especially bad in moist air? A) absorptive attenuation B) electromagnetic interference C) multipath interference D) inverse square law attenuation

absorptive attenuation

85) Because of ________, an 802.11AX access point can communicate with an 802.11AY client. A) MIMO B) MU-MIMO C) backward compatibility D) They CANNOT communicate.

backward compatibility

42) 802.11 operates in the ________ unlicensed service band. A) 2.4 MHz B) 60 MHz C) both A and B D) neither A nor B

both A and B

50) Which of the following uses OFDM? A) 802.11ac B) 802.11n C) both A and B D) neither A nor B

both A and B

62) Media access control governs transmission by ________. A) access points B) wireless hosts C) both A and B D) neither A nor B

both A and B

81) Beamforming can allow an access point to ________. A) focus power on individual clients B) send signals to two different clients at the same time C) both A and B D) neither A nor B

both A and B

92) Which of the following is true of 802.11ay over 802.11ad? A) greater propagation speed B) greater propagation distance C) both A and B D) neither A nor B

both A and B

33) To transmit data very rapidly, you would want a ________ channel. A) narrowband B) broadband C) single-frequency band D) single-mode

broadband

34) Channels with wide bandwidths are called ________ channels. A) multimode B) full-duplex C) broadband D) parallel

broadband

64) In CSMA/CA, CS means ________. A) cancel sending B) counter-source C) carriage suspension D) carrier sense

carrier sense

27) An FM radio station is called Moldy Oldies 101.1. The 101.1 refers to its ________. A) single frequency B) channel C) service band D) none of the above

channel

25) To handle multiple conversations in 802.11 transmission, you normally use multiple ________. A) channels B) frequencies C) service bands D) wires

channels

31) If you want to transmit 7 times as fast in radio, you need to use ________. A) channels that are about 7 times as wide B) channels that are about 49 times as wide C) spread spectrum transmission D) none of the above

channels that are about 7 times as wide

10) Wireless radio transmission speed is usually measured in terms of ________. A) wavelength B) frequency C) amplitude D) dollars

frequency

49) Spread spectrum transmission's wider channels brings ________. A) greater speed B) greater reliability C) greater security D) none of the above

greater reliability

73) Wider channel bandwidth ________. A) increases transmission speed B) allows more channels to be used in a service band C) both A and B D) neither A nor B

increases transmission speed

41) Two access points that operate on the same channel will ________. A) bond B) coordinate their use of the channel C) interfere D) divide the available spectrum about equally

interfere

46) If you triple channel bandwidth, what happens to the number of channels in a service band? A) It triples. B) It increases by a factor of nine. C) It is reduced a third. D) It is reduced a ninth.

it is reduced a third

47) Spread spectrum transmission is used in WLANs because ________. A) it is required by regulators B) it offers strong security C) both A and B D) neither A nor B

it is required by regulators

61) ________ is a technique for preventing two wireless stations from interfering with each other by transmitting at the same time. A) Creating extended service sets B) Roaming C) The distribution system D) Media access control

media access control

45) Companies prefer the 5 GHz band because there is ________ than in the 2.5 GHz band. A) more bandwidth B) less absorptive attenuation C) both A and B D) neither A nor B

more bandwidth

48) Spread spectrum transmission is used in WLANs for ________. A) higher transmission speed B) more reliable transmission C) greater security D) more efficient transmission

more reliable transmission

89) The 60 GHz unlicensed service band offers ________ compared to lower-frequency service bands. A) more speed per channel B) greater propagation distance C) greater ability to penetrate walls D) all of the above

more speed per channel

13) If another wireless device is near, but in an unknown direction, it is better to use ________. A) an omnidirectional antenna B) a dish antenna C) neither A nor B

an omnidirectional antenna

35) The term "broadband" is commonly used for ________. A) wide radio bandwidths B) high-speed transmission in general C) both A and B D) neither A nor B

both A and B

20) The most serious problem with wireless transmission in WLANs is ________. A) inverse square law attenuation B) absorptive attenuation C) shadow zones D) multipath interference

multipath interference

58) In an extended service set, each access point ________. A) must have the same SSID B) must have a different SSID C) must have a coordinated SSID D) none of the above

must have the same SSID

38) Wi-Fi standards use unlicensed bands for ________ A) greater speed B) greater standardization C) greater flexibility D) greater privacy

greater flexibility

79) MIMO ________. A) increases throughput B) lowers propagation distance C) both A and B D) neither A nor B

increases throughput

22) What propagation problem becomes worse as frequency increases? A) inverse square law attenuation B) electromagnetic interference C) both A and B D) neither A nor B

neither A nor B

14) Wi-Fi normally uses a(n) ________. A) omnidirectional antenna B) dish antenna C) both A and B D) neither A nor B

omnidirectional antenna

86) An 802.11ac Wi-Fi compatibility testing profile contains ________ of the features of the 802.11ac. A) all B) nearly all C) some D) none

some

24) In Wi-Fi, 2.4 GHz and 5 GHz refer to ________. A) frequency spectrums B) broadbands C) channels D) none of the above.

none of the above

44) In general, the fewer the channels, ________. A) the greater the likelihood of interference between access points B) the smaller the individual channels will be C) both A and B D) neither A nor B

the greater the likelihood of interference between access points

30) What is the bandwidth of a channel that extends from 55 MHz to 60 MHz? A) 60 MHz B) 55 MHz C) 65 MHz D) none of the above

none of the above

36) WLANs normally use ________. A) licensed bands B) unlicensed bands C) both A and B D) neither A or B

unlicensed bands

32) To transmit very rapidly in radio, you need ________. A) single-frequency transmission B) single-mode transmission C) wide bandwidth D) narrow bandwidth

wide bandwidth

52) A wireless host sends a packet to a server on the company's wired Ethernet LAN via an access point. How many frames will be involved in this one-way transmission? A) 1 B) 2 C) 4 D) There will be one frame for each switch along the way.

2

43) The 2.4 GHz band supports ________ possible non-overlapping 20 MHz channel(s). A) 1 B) 3 C) 7 D) 11

3

3) Wi-Fi Standards come from the ________ Working Group. A) 802.1 B) 802.3 C) 802.11 D) 802.1X

802.11

5) We use the terms Wi-Fi and ________ interchangeably in this book. A) 802.1 B) 802.3 C) 802.11 D) 802.1X

802.11

51) Access points take ________ from wireless devices and send them on to devices on the wired LAN. A) packets B) frames C) both A and B D) neither A nor B

packets