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Preguntas del test (102)
1Which of the following is not a characteristic of IEEE 802. 11a?
- AThe fastest speed is 54 Mbps with an optional proprietary speed of 108 Mbps
- BIt uses ISM instead of UNII
- CThe range of coverage is less than 802. 11b
- DThe bandwith is 300 MHz.
2The abbreviation (µs) stands for
- Amicroseconds
- Bmilliseconds
- Cnanoseconds
- Dkiloseconds
3Each of the following is an advantage of spread-spectrum transmissions except
- AHigher power requirements
- BMore information transmitted
- CResistance to narrowband interference
- DResistance to multipath distortion
4The PLCP frame preamble and header in 802. 11b are always transmitted at _____ Mbps.
- A5. 5
- B1
5_____ is the difference between the upper and lower frequencies.
- AGuard interval
- BBandwidth
6Each of the following is a type of spread-spectrum technology except
- AUNII
- BOFDM
- CDSSS
7The ability to adjust the "quiet" period between OFDM symbols to allow for the arrival of late symbols in 802. 11n is called
- Aspace allocation
- Bvariable guard interval (VGI)
8Two safeguards to protect 802. 11n channel bonding from interfering with other WLANs are Dynamic Frequency Selection (DFS) and ___
- AMIMO Substitution
- BMIMO Branching (MIBRA)
- CPhased Coexistence Operation (PCO)
9Each of the following channels is a nonoverlapping frequency in 802. 11b except
- A11
- B8
10All of the possible combinations of different factors for 802. 11n transmissions are contained in the
- AIEEE 802. 11n Resource Guide
- BModulation and Coding Scheme (MCS)
- CUNII Procedures Manual
11Which of the following is another name for the expanded redundant code used by DSSS?
- AModulation and Coding Scheme
- BBarker code
- Chopping code
12A frame is made up of which parts? (Choose all that apply.)
- Asegment
- Bpreamble
- Cdata
- Dheader
13Which of the following sublayers makes up the standards for the characteristics of the wireless medium and defines the method for transmitting and receiving data through that medium?
- APhysical Layer Convergence Procedure sublayer
- BPhysical Medium Dependent sublayer
14Which of the following is a numeric value assigned to a frequency range?
- Abandwidth
- Bchannel
15How does OFDM work?
- Aone signal is sent twice on the same channel
- Bsignals are broken up and the parts are sent in parallel
- Ca signal is sent over a wired network at the same time as the wireless network
16The passive gain increase of power that is funneled from an antenna compared to that of an isotropic radiator is called
- AdBp
- BdBi
17The maximal ratio combining (MRC) algorithm is used when
- Aa MIMO device sends to a MIMO device
- Ba MIMO device sends to a non-MIMO device
- Ca non-MIMO device sends to a MIMO device
18Another name for system operating margin (SOM) is
- Areserve margin
- Bfade margin
- Cadditive margin
19A SISO system has how many radio chains?
- A3
- B1
20A wireless device designated as 2x3:1 has how many Rx antennas?
- A3
- B2
21A(n) _____ chart shows the vertical coverage area of an antenna.
- Ameter
- Belevation
22The orientation of radio waves as they leave an antenna is called
- Aorientation
- Bpolarization
23When the VSWR is indicated in dB it is called the
- Adownfade
- Breturn loss
- Cpower ratio
24An antenna that divides the entire 360 degrees of coverage area into eight sectors of 45 degrees each is called a(n)
- APhased Dipole Array Configuration (DPAC)
- Bsectorized antenna
25The general rule of thumb is that _____ percent of the first Fresnel zone must be clear of obstacles.
- A90
- B60
- C75
26Which of the following are signaling processing techniques used by MIMO to create high throughput? (Choose all that apply.)
- Aspatial multiplexing
- Btransmit beam forming
- Cmaximal ratio combining
- Dspatial singularity
27Which is a type of amplifier that can be used to boost an RF signal?
- Abidirectional amplifier
- Bsemi-directional amplifier
- Comnidirectional amplifier
- Dquasi-directional amplifier
28Which of the following are among the basic categories of antenna? (Choose all that apply.)
- Asemidirectional
- Bunidirectional
- Comnidirectional
- Dhighly-directional
29Which of the following terms describes a material that allows an electrical current to flow through it?
- Aisotropic radiator
- Bconductor
30The technique for combating multipath by using multiple transmit and receive antennas is sometimes called which of the following?
- AMIMO diversity
- Btransmit beam forming
- Cnulling
31A(n) _____ describes a specific unit of data that has been passed down from a higher OSI layer to a lower layer but has not yet been encapsulated by that lower layer.
- AExtended MAC Protocol Data Unit (X-MPDU)
- BService Data Unit (SDU)
- CAggregate Data Unit (ADU)
32How many different service sets are available in IEEE 802. 11?
- Afour
- Bthree
33____ reserves the medium for a period of time and handles the hidden node problem.
- ARequest to Send/Clear to Send (RTS/CTS)
- BCarrier Sense Multiple Access with Collision Detection (CSMA/CD)
34What happens if a probe request frame contains a null value?
- AOnly APs with a null SSID will respond.
- BNo APs will respond.
- CAll APs will respond.
35Each of the following is an option for addressing differences in frame size except
- AJumbo Frames
- Bmaximum transmission unit splicing (MTUS)
36Which of the following is the default access method for IEEE 802. 11 WLANs?
- ACarrier Sense Multiple Access with Collision Detection (CSMA/CD)
- BCarrier Sense Multiple Access with Collision Avoidance (CSMA/CA)
- CCarrier Sense Multiple Access with Collision Routing (CSMA/CR)
- DCarrier Sense Multiple Access with Collision Mitigation (CSMA/CM)
37A(n) _______ consists of one or more stations that are served by a single access point.
- AHybrid Service Set (HSS)
- BBasic Service Set (BSS)
38The hybrid coordination function (HCF) allows for different types of wireless traffic to be given different levels of _____.
- Abackoff procedures
- Bpriority
- Cframe size
39Which of the following uses a challenge text?
- AOpen system authentication
- BShared key authentication
40_____ is when the AP transmits its beacon frame and a station is looking for those frames.
- AWLAN resource allocation
- BBeacon reconnaissance (BR)
- CPassive scanning
41When an AP accepts or rejects a wireless device it sends a(n) ____ frame.
- Aauthentication
- Bassociation response
- Cassociation request
42Which of the following are wireless LAN service set configurations? (Choose all that apply.)
- Abasic service set
- Bextended service set
- Cindependent basic service set
- Dadvanced service set
43Following authentication, if the access point accepts the wireless device, it reserves memory space in the AP and establishes a(n) ____ ID for it.
- Amember
- Bauthentication
- Cassociation
44At regular intervals the AP sends a ____ frame to both announce its presence and to provide the necessary information for other devices to join the network.
- Abeacon
- Bcontrol
45In which HT Operation Mode do all stations use the 802.11a/b/g format to ensure backward compatibility?
- AHT 20 MHz Protection Mode
- BHT Greenfield Mode
- CHT Nonmember Protection Mode
46An intentional radiator (IR) is
- APower directed from an antenna
- BPower directed to an antenna
47___ is the power radiated out by the wireless system and includes any antenna gain.
- AEquivalent Isotopically Radiated Power (EIRP)
- BRadiation Power (RP)
48The passive gain increase of power that is funneled from an antenna compared to that of an isotropic radiator is called
- AdBi
- B.
49Compares the antenna gain against that of a dipole antenna
- AdBd
- B.
50The orientation of radio waves as they leave an antenna.
- APolarization
- BPhase
51AP's with multiple antennas employ _____ to improve reception
- AAntenna Diversity
- B.
52Generally, A semidirectional antenna will only transmit its signal no more then _______ degrees
- A90
- B180
53An antenna that divides the entire 360 degrees of coverage area into eight sectors of 45 degrees each is called a(n)
- ADipole Antenna
- BSectorized Antenna
54The outer circle of an antenna radiation chart represents
- Aa gain that is 100 percent
- Bthe location of an antenna
55A(n)_____chart shows the vertical coverage area of an antenna
- Aelevation
- Bazure
56Beamwidth is considered a measure of the antenna's ________range
- Afull-power
- Bhalf-power
57The general rule of thumb is that_____percent of the 1st fresnel zone must clear of obstacles
- A60
- B45
58A SISO system has how many radio chains
- A3
- B1
59_____sends redundant streams in parallel
- Aspatial diversity
- Bsiso diversity
60a wireless device designated as 2x3:1 has how many rx antennas
- A3
- B5
61The maximal radio combining (MRC) alogorithm is used when
- AMIMO devicesends to a non-MIMO device
- Ba non-MIMO device sends to MIMO device
62what are 3 good locations for installing AP
- Aceiling
- Bnone
- Chigh on a wall
- Da pole
63Amplifiers for wireless LANs are
- Aundirectional
- Bbidirectional
64Another name for system operating margin (SOM) is
- Afade margin
- Bbuffer space
65When the VSWR is indicated in DB it is called the
- ADownfade
- BReturn Loss
66What is an advantage of narrowband transmission
- Athe amount of spectrum used
- Binterference
67Each of the following is and advantage of spread-spectrum transmission except
- Ahigher power requirements
- Bmore information transmitted
68Each of the following is a spread-spectrum technology except
- AUNII
- BOFDM
69____is the difference between the upper and lower frequencies
- Abandwidth
- Bguard interval
70In FHSS the amount of time used to change from one frequency to the next is called the
- APhase
- BHop Time
71What technology us a chipping code
- ADSSS
- BFHSS
72When using____each device is assigned a unique chipping code in order that all the transmission can use the same frequency yet remain separate
- AColocation
- BShared Bandwidth
73With OFDM, the____is intended to reduce intersymbol interference (ISI)
- APresymbol Response
- BGuard Interval
74The____sublayer reformats the data received from the higher layer into a frame that can be transmitted
- Atransmitted
Physical Layer Convergence Procedure (PLCP) - BLogical Link Control (LLC)
- Atransmitted
75
DSS is used by- A802.11b
- B802.11a
76The PLCP frame preamble and header in 802.11b are always transmitted at____Mbps
- A5.5
- B1
77Each of the following channels is a nonoverlapping frequency in 802.11b except
- A8
- B6
78Which of the following is not a characteristic of IEEE 802.11a
- AIt uses ISM instead of UNII
- BThe bandwidth is 300 MHz
79_____transmit a secondary copy along with primary information to account for errors
- AForward Error Correction (FEC)
- BMultiplexing
80How many nonoverlapping channels are available in IEEE 802.11a
- A12
- B23
81Two Safeguards to protect 802.11n channel bonding from interfering with other WLANs are dynamic frequency selection (DFS) and_____
- Aphased coexistence operation (PCO)
- BMIMO Substitution
82
The ability adjust the "Quiet" period between OFDM symbols to allow for the arrival of late symbol in 802.11n is called- AVariable guard interval (VGI)
- BSpace Allocation
83All of the possible combinations of different factors for 802.11n transmissions are contained in the
- Amodulation and coding scheme (MCS)
- BUNII Procedures Manual
84The abbreviation us stands for
- AMicroseconds
- BMilliseconds
85A numeric value that is assigned to a frequency range called the
- AModulation
- BChannel
86
How many differnet service sets are available in IEEE 802.11- AThree
- BFive
87A(n)_____consists of one or more stations that are served by a single access point
- AHybrid Service Set (HSS)
- BBasic service sets (BSS)
88Each of the following is a name for a service that that does not use an AP except
- APeer-to-peer
- BBasic Service Set
89A(n)_____describes a specific unit of data that has been passed down from a higher OSI layer to a lower layer but has not yet been encapsulated by the lower layer
- AService Data Unit (SDU)
- BAggregate Data Unit (ADU)
90What is a restriction that applies to A-MPDU
- AAll of the A-MPDU within the single A-MPDU must be addressed to the same receiver
- BThey cannot use OFDM
91Each of the following is an option for addressing differences in frame size except
- Ajumbo frames
- Bmaximum transmission unit splicing (MTUS)
92In____made an IEEE 802.11a/b/g device will not be able to access the AP
- AHT Mixed
- BGreenfield
93___frames are used to set up initial communications between device and access point
- AData
- BManagement
94____is when AP transmit its beacon frame and a station is looking for those frames
- APassive Scanning
- BSSID allocation
95What happens if a probe request frame contains a null value
- AAll AP's will respond
- BNo AP's will respond
96____is the process in which an AP accepts a station into WLAN
- AAutentication
- BAuthorization
97Which of the following is false regarding block acknowledgement
- AIt only applies to 802.11n
- BThe sender then will retransmit all MPDU's
98What is used when 802.11g devices are mixed with 802.11b devices together
- ACTS-To-self
- BRTS/GHS
99What interframe spaces is used for immediate response actions such as ACK and has the highest levels of priority
- AShort IFS (SIFS)
- BArbitration IFS (AIFS)
100_____is an optional polling mechanism
- APolling Contact
- Bpoint coordination function (PCF)
101The hybrid coordination funtion (HCF) allows for different types of wireless traffic to be given different levels of_____
- Apriority
- Bspeed
102Each of the following is an Enhanced Distributed Channel Access (EDCA) access category (AC) except
- ABest effort (AC_BE)
- BForeground (AC_FG)
Información
- Descripción
- Test sobre Sin título, creado por Robert Fredricks el 31/05/2016.
- Autor
- Robert Fredricks
- Idioma
- English
- Visitas
- 0
- Valoración
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