CWNA-108 実際試験問題と解答 - 模擬練習 - 受験自信を増やす

Question No : 1
An 802.11-based network uses an AP and has several connecting clients. The clients include iPhones, iPads, laptops and one desktop.
What WLAN use case is represented?

A.Ad-hoc
B.WPAN
C.BSS
D.IBSS

正解:

Question No : 2
Which IEEE 802.11 physical layer (PHY) specification includes support for and compatibility with both ERP and HR/DSSS?

A.DSSS (802.11-Prime)
B.OFDM (802.11a)
C.HT (802.11n)
D.VHT (802.11ac)

正解:

Question No : 3
What statement is true concerning the use of Orthogonal Frequency Division Multiplexing (OFDM) modulation method in IEEE 802.11 WLANs?

A.OFDM implements BPSK modulation to allow for data rates up to 7 Gbps.
B.OFDM was first introduced in 802.11a and is used by the ERP, HT and VHT PHYs as well.
C.OFDM modulation is used only in 5 GHz 802.11 transmissions.
D.OFDM was used by Frequency Hopping Spread Spectrum (FHSS) PHY devices.

正解:

Question No : 4
You are implementing a VHT-capable AP.
Which one of the following channels is available in the 802.112016 standard that was not available before the ratification of 802.11 ac?

A.56
B.161
C.153
D.144

正解:

Question No : 5
An IEEE 802.11 amendment is in the daft state.
What impact does this draft amendment have on the 802.11 standard?

A.Devices will be released based on the draft amendment and the draft amendment features are part of the standard.
B.No impact: Until an amendment is ratified, it does not become part of the standard.
C.No impact: Draft amendments do not become part of the standard until a working group is formed.
D.The standard is changed to reflect the new capabilities as soon as an amendment enters the draft stage.

正解:

Question No : 6
What best describes WPA2 in relation to 802.11 wireless networks?

A.WPA2 is the standard that defines security for WLANs.
B.WPA2 is a certification created by the Wi-Fi Alliance that validates devices correctly implement CCMP/AE
C.WPA2 is the second version of WPA and it enhances security through the use of TKIP instead of WE
D.WPA2 is specified in the 802.11 standard as implementing CCMP/AE

正解:

Question No : 7
Which one of the following is not a factor considered when calculating the Link Budget for an outdoor point-to-point WLAN bridge link?

A.Operating frequency
B.MU-MIMO capabilities of the bridges
C.Receive antenna gain
D.Transmit power

正解:

Question No : 8
What statement about the beamwidth of an RF antenna is true?

A.Horizontal and vertical beamwidth are calculated at the points where the main lobe decreases power by 3 d
B.The beamwidth patterns on an antenna polar chart indicate the point at which the RF signal stops propagating.
C.When antenna gain is lower, the beamwidth is also lower in both the horizontal and vertical dimensions.
D.Vertical beamwidth is displayed (in degrees) on the antenna’s Azimuth chart.

正解:

Question No : 9
Which directional antenna types are commonly used by indoor Wi-Fi devices in a MIMO multiple spatial stream implementation?

A.Dipole and yagi
B.Grid and sector
C.Patch and panel
D.Dish and grid

正解:

Question No : 10
What wireless networking term describes the increase of RF energy in an intentional direction with the use of an antenna?

A.Directed Radiation
B.Beam Digression
C.Passive Gain
D.Active Amplification

正解:

Question No : 11
In a long-distance RF link, what statement about Fade Margin is true?

A.A Fade Margin is unnecessary on a long-distance RF link if more than 80% of the first Fresnel zone is clear of obstructions.
B.The Fade Margin is a measurement of signal loss through free space and is a function of frequency and distance.
C.Fade Margin is an additional pad of signal strength designed into the RF system to compensate for unpredictable signal fading.
D.The Fade Margin of a long-distance radio link should be equivalent to the receiver’s low noise filter gain.

正解:

Question No : 12
A WLAN transmitter that emits a 50 mW signal is connected to a cable with 3 dB loss.
If the cable is connected to an antenna with 9dBi gain, what is the EIRP at the antenna element?

A.26 dBm
B.13 dBm
C.23 dBm
D.10 dBm

正解:

Question No : 13
What factor does not influence the distance at which an RF signal can be effectively received?

A.Receiving station’s radio sensitivity
B.Receiving station’s output power
C.Transmitting station’s output power
D.Free Space Path Loss

正解:

Question No : 14
What can an impedance mismatch in the RF cables and connectors cause?

A.Increased range of the RF signal
B.Fewer MCS values in the MCS table
C.Increased amplitude of the RF signal
D.Excessive VSWR

正解:

Question No : 15
An RF signal sometimes bends as it passes through some material other than free space.
What is the term that describes this behavior?

A.Refraction
B.Warping
C.Scattering
D.Reflection

正解:

CWNP CWNA-108 問題練習