CWNA Research & Evidence-Based Practice 4

Question 1

A wireless engineer uses a protocol analyzer to capture 802.11 management frames. Which frame type provides evidence that a client is actively scanning for networks?

Accepted Answer

Probe Request frames

Answer

Probe Request frames are transmitted by clients actively scanning for available networks, making them the direct evidence of client scanning behavior.

Question 2

A wireless team finds conflicting SNR thresholds recommended by two different vendors for VoWiFi deployments. What is the most evidence-based way to resolve this conflict?

Accepted Answer

Test both thresholds in a representative environment and measure call quality metrics (MOS, jitter, packet loss)

Answer

Empirically testing both thresholds against objective voice quality metrics (MOS, jitter) in the actual environment resolves vendor conflicts with direct evidence.

Question 3

Which 802.11 standard amendment introduced BSS Coloring as a mechanism to reduce co-channel interference, and what evidence supports its effectiveness?

Accepted Answer

802.11ax (Wi-Fi 6); reduced OBSS/SR collisions measurable via protocol analysis and throughput testing

Answer

BSS Coloring was introduced in 802.11ax to allow nodes to identify overlapping BSS frames and reduce unnecessary deferrals, with effectiveness verifiable through protocol capture and throughput measurement.

Question 4

A network analyst wants to determine whether 802.11r Fast BSS Transition is functioning correctly after deployment. Which evidence confirms successful operation?

Accepted Answer

Protocol analyzer showing FT Action frames and sub-50ms reassociation times during roam events

Answer

FT Action frames captured in a protocol analyzer, combined with measured reassociation timing, provide direct evidence that 802.11r is operating correctly.

Question 5

A hospital wireless team is designing a policy for clinical device roaming. Which approach best represents evidence-based practice for determining minimum RSSI thresholds?

Accepted Answer

Test clinical devices in representative RF conditions and record the RSSI at which application performance degrades

Answer

Testing actual clinical devices under real RF conditions and correlating RSSI with application performance degradation provides device-specific, empirically grounded thresholds.

CWNA - Wireless Network Administrator Practice Test

CWNA - Wireless Network Administrator Practice Test

CWNA Research & Evidence-Based Practice 4