Online Access Free PW0-270 Exam Questions

What must occur before an HT STA operating in an EDCA BSS can transmit a data frame over the wireless medium? (Choose 3)

• A.Its CCA must report that the medium is idle.
• B.The STA must receive a BlockAck, resetting the NAV to zero.
• C.Its NAV must be equal to one.
• D.The backoff timer for the AC must equal zero.
• E.The appropriate interframe space must expire.
• F.The AP must issue the STA a TXOP.

Which statements are true regarding Beacons from an AP in an HT infrastructure BSS that is configured with multiple WLAN profiles? (Choose 3)

• A.The Destination Address is always FF:FF:FF:FF:FF:FF.
• B.The Receiver address and the BSSID are always the same.
• C.The Beacon interval must be the same for all WLANs (SSIDs) supported by a single AP
• D.When the SSID is "hidden," the ESS subfield of the Capability Information field distinguishes one BSS from another.
• E.All Beacons generated by APs contain a TIM information element.
• F.Beacons can be disabled for security purposes.
• G.The BSSID and Source Address are always the same.

ABC Company is having VoWiFi latency problems on their 802.11g WLAN. A wireless administrator has noticed in the phone's client utilities software that the MAC CRC Error count is higher on stations with problems than on those client stations without problems.
A high MAC CRC Error count is attributable to which of the following? (Choose 3)

• A.2.4 GHz ISM band interference from sources such as wireless video cameras and analog phones
• B.High multipath conditions due to an RF environment with highly reflective materials
• C.High collision rates due to dense population of voice stations and no admission control
• D.Dynamic Rate Switching algorithms that decrease data rates for latency-sensitive applications
• E.Co-located DCF and EDCA access points that are using non-overlapping 2.4 GHz channels
• F.Two access points with overlapping coverage on a single channel

ABC Company's WLAN administrator is getting complaints from one user that his WLAN throughput is sluggish compared to other users in his area. The administrator takes his diagnostics laptop, which has a wireless protocol analyzer installed, to the area where the complaining user works. The administrator uses the PING utility to test connectivity from the complaining user's wireless client station to another wireless client station across the closest access point, while capturing the wireless frames. The administrator sees what is displayed in this screenshot.

From this screenshot, which statements can you conclude to be TRUE that are related to the complaining user's throughput problem? (Choose 2)

• A.The complaining user's station is retransmitting fragments many times likely due to nearby RF interference.
• B.The access point and other stations are using ERP-OFDM modulation, and the complaining user's wireless client station is using HR/DSSS modulation.
• C.The complaining user's WLAN client utilities are configured with a small fragmentation threshold.
• D.The complaining user's wireless client station should be using RTS/CTS as a protection mechanism, but it is not.
• E.The access point is not signaling for protection (Protection = no) in the Beacons, but it should be.

The 802.11r-2008 amendment to the 802.11 specification introduces what new Information Elements (IEs) to facilitate fast BSS transitions? (Choose 2)

• A.RSN IE (Robust Security Network)
• B.FSR IE (Fast Secure Roaming)
• C.MD IE (Mobility Domain)
• D.DS IE (Distribution System)
• E.HT IE (High Throughput)
• F.FT IE (Fast Transition)