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A. The RA field of ACK frames is always obtained from the Address 2 field in the corresponding frame being acknowledged.

B. Data frame fragments are acknowledged individually (with an ACK frame).

C. Following non-QoS Data frames with the More Fragments bit set to 1, the Duration/ID field of the ACK frame is set to a value equal to two SIFS plus the next Data fragment and its ACK.

D. Probe request acknowledgement (sending of a Probe Response frame) is configurable in the access point and is always linked to SSID broadcast configuration in Beacons.

E. In an EDCA BSS, encrypted Data frames are only acknowledged by client stations, never by access points.

F. A client station's Reassociation Request frames are only acknowledged with a Reassociation Response from the access point and not with an ACK frame.

A. A CTS-to-Self frame sent by a client station may reach fewer nodes than the RTS/CTS frame exchange.

B. RTS and CTS frames are relayed through the access point, whereas the CTS-to-Self frames are not.

C. By definition, all associated client stations in a BSS can hear RTS, CTS, and CTS-to-Self frames, so RTS/CTS and CTS-to-Self mechanisms have equal effectiveness.

D. Aside from the Subtype subfield of the Frame Control field, the generic MAC header format of RTS and CTS frames are identical.

E. Use of RTS/CTS requires more overhead than CTS-to-Self due to a higher number of frames transmitted onto the wireless medium.

F. RTS and CTS frames use Short Interframe Spaces (SIFS), and CTS-to-Self frames use PCF Interframe Spaces (PIFS).

A. Only when a STA roams back to an AP it has previously been associated with

B. Every time a STA roams

C. Only when a STA is using FT roaming

D. Every time a STA associates to an AP to which it has previously been associated

A. BlockAck Reset

B. Authentication Failure

C. Contention Window

D. ACK Timeout

E. Retransmission Count

F. Duration value

A. Its NAV must be equal to one.

B. The STA must receive a BlockAck, resetting the NAV to zero.

C. The backoff timer for the AC must equal zero.

D. The appropriate interframe space must expire.

E. Its CCA must report that the medium is idle.

F. The AP must issue the STA a TXOP.

A. The proprietary encryption protocol will have no effect on your troubleshooting steps because the wireless protocol analyzer can still decode the PLCP and MAC headers of Data frames. This situation is essentially no different than troubleshooting a WLAN that uses WPA2-Personal.

B. Troubleshooting will be somewhat limited because only part of the information needed for performance measurements by the analyzer is encrypted. Each Data frame's MAC header will be encrypted, but the PLCP header can still be decoded successfully.

C. As long as you load the proprietary software codec onto your analyzer computer, you will be able to see all of the Data frame information fully decoded. Loading the proprietary software codec will allow you to troubleshoot the WLAN as though no encryption were in use.

D. In order to troubleshoot performance problems on a network using proprietary encryption protocols like this one, you must use a wireless protocol analyzer that has integrated support for the protocol in use.

A. RSN-IE

B. Address 4

C. HT Control

D. QoS Control

A. CTS

B. RTS

C. Ack

D. Block Ack

A. To DS = 1, From DS = 0

B. To DS = 0, From DS = 0

C. To DS = 1, From DS = 1

D. To DS = 0, From DS = 1

A. HE MU PPDU

B. HE SU PPDU

C. VHT PPDU

D. HE TB PPDU

A. Real-Time FFT

B. Interferer Count

C. Swept Spectrogram

D. FFT Duty Cycle

E. SNR