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