Which statement is true regarding the Association Identifier (AID) used in IEEE 802.11 WLANs?
A. The AID has a maximum value of 2048, and is used to uniquely identify a wireless client station associated with an access point.
B. The AID has a maximum value of 2007, and resides in the duration/ID field of a PS-Poll frame.
C. The client station is assigned an AID value in the 802.11 authentication response frame.
D. The AID field is present only in Beacons frames.
E. The AID is used by the access point in EDCA mode to reduce duplicate transmissions when sending multicasts.
The Retry subfield is found in which IEEE 802.11 frame field?
A. Sequence Control field
B. Protocol Order field
C. Data Control field
D. Frame Control field
E. MAC Service Data Unit field
F. QoS Control field
An HT STA does not receive an ACK for a first-attempt data frame that it transmitted. Assuming this STA is not using BlockAcks in this case, what happens to the HT STA's EDCA contention window?
A. The slot time within the contention window decreases by 50%.
B. It varies because the backoff algorithm is random.
C. The contention window approximately doubles in size.
D. The contention window is not affected by failed Data frame delivery.
E. The contention window is immediately closed, and the frame is retransmitted.
Which statements are true regarding wireless network discovery and scanning processes for an HT network? (Choose 2)
A. Client stations may continually send Probe Request frames on all HT channels in the 2.4 GHz ISM band in a consecutive manner, regardless of their association state.
B. Access points send Beacon frames on all HT channels in the 2.4 GHz ISM band in a consecutive manner including the channel for which the access point is configured.
C. Client stations send Probe Request frames on all HT channels in the 2.4 GHz ISM band in a consecutive manner until they associate with an access point. After associating to an access point, they no longer transmit Probe Request frames.
D. Access points send Beacon frames only on the HT channel in the 2.4 GHz ISM band for which the access point is configured, and only after scanning that channel to discover existing BSSs.
E. Client stations send Probe Request frames on all HT channels in the 2.4 GHz ISM band in a consecutive manner until they receive at least 3 Probe Response frames.
WMM-PS trigger frames can be what type of IEEE 802.11 frames? (Choose 2)
A. QoS Null
B. Reassociation
C. QoS Data
D. CTS
E. QoS Action
F. PS-Poll
As it pertains to HT L-SIG TXOP Protection, what statement is true?
A. Support for L-SIG TXOP Protection is indicated by HT stations in the L-SIG field of the PLCP header of HT-mixed format frames.
B. Support for L-SIG TXOP Protection is indicated in the HT Capabilities Info field of (re)association request frames sent by ERP, OFDM, and HT-OFDM stations.
C. An L-SIG TXOP protected frame exchange sequence always begins with an RTS/CTS or a CTS-to- Self.
D. L-SIG TXOP Protection is specified for the purpose of protecting OFDM (802.11a/g) and HT- OFDM (802.11n) transmissions from HR/DSSS stations.
Many access points support IEEE 802.1Q VLAN tagging. When analyzing a WLAN system using IEEE 802.1Q tags, where can the VLAN tag number be seen?
A. In the Sequence Control field of the MSDU
B. In the PLCP header's Service field
C. In the Frame Control field of the MPDU header
D. In the Ethernet header on the wired port of the access point
E. In the Beacon Management frame's Capabilities fixed field
Given: Before installing a Wi-Fi network, ABC Company performed a spectrum analysis looking for problems. The 2.4 GHz RF spectrum looked like Image-A. After installing an ERP WLAN, ABC Company performed another spectrum analysis during business hours. The 2.4 GHz RF spectrum then looked like Image-B close to an AP on channel 1.
Now the 2.4 GHz RF spectrum looks like Image-C and access points and clients can no longer communicate on channel 1. What is happening on channel 1?
A. The access point's antenna connectors have been tampered with, causing "spike and shear" RF transmissions that are not compatible with the OFDM PHY format. For that reason, client devices cannot receive the AP's transmissions without error.
B. A high-power, narrowband RF interference source on channel 1 is causing the CCA energydetects(ED) function on 802.11 devices to indicate a busy medium because the signal source is above the ED threshold.
C. Stronger transmissions from licensed 2.4 GHz users, such as HAM operators, are compressing the transmissions from the channel 1 access points into the lower portion of the band.
D. The shape of the signals in images B and C indicates that a licensed user in this frequency range has enabled the "guard bands" in an effort to restrict local interference with other systems.
E. Detection of a DFS radar event has discontinued 802.11 operation on channel 1, but the access point's Channel Switch Announcement frame cannot be sent due to the presence of radar.
As it relates to a spectrum analyzer, complete the following sentence.
The ____________ plot always displays the percentage of time (shown on the Y axis) that the overall RF power is a certain specified threshold (of amplitude) above the noise floor for a given frequency range (shown on the X axis).
A. Real-Time FFT
B. Swept Spectrogram
C. FFT Duty Cycle
D. Interferer Count
E. SNR
Given the screenshot shown, Choose the statement that accurately describes what is being seen by this protocol analyzer.
A. Three access points are on the same channel in the same physical area.
B. A Single Channel Architecture (SCA) WLAN solution has three WLAN profiles configured
C. One access point is using the 802.11 round robin Beacon feature.
D. Three wireless stations are participating in an Ad Hoc WLAN.