CWNA Research & Evidence-Based Practice 5 — Questions and Answers
Question 1: A CWNA professional is asked to prove that a recent firmware update improved network performance. Which research practice ensures a valid conclusion?
- Compare user complaints before and after the update
- Collect baseline performance metrics before the update and compare identical metrics after deployment (Correct answer)
- Ask the vendor if the firmware is better
- Observe whether users seem happier after the update
Correct answer: Collect baseline performance metrics before the update and compare identical metrics after deployment
Collecting identical quantitative metrics before and after the change creates a controlled comparison that isolates the firmware's effect on performance.
Question 2: A wireless engineer is evaluating OFDMA efficiency gains in a dense environment. Which evidence directly demonstrates OFDMA's impact on airtime utilization?
- The number of clients connected to the AP
- Airtime utilization percentage measured before (OFDM) and after (OFDMA) enabling the feature under equivalent load (Correct answer)
- AP CPU utilization stats
- Physical layer data rate shown in the client adapter properties
Correct answer: Airtime utilization percentage measured before (OFDM) and after (OFDMA) enabling the feature under equivalent load
Measuring airtime utilization under equivalent load before and after enabling OFDMA directly quantifies its efficiency improvement on the wireless medium.
Question 3: Which wireless troubleshooting framework most closely follows the evidence-based practice model?
- Apply the most common fix immediately and see if it resolves the issue
- Define the problem, collect data, form a hypothesis, test it, and validate the outcome (Correct answer)
- Escalate to the vendor whenever a problem appears
- Reboot all APs and observe whether complaints stop
Correct answer: Define the problem, collect data, form a hypothesis, test it, and validate the outcome
The define-collect-hypothesize-test-validate cycle mirrors the scientific method and ensures decisions are guided by data rather than assumptions.
Question 4: A wireless architect references the Wi-Fi Alliance's Wi-Fi 7 certification program requirements. What is the primary research value of this document?
- It lists which vendors sell Wi-Fi 7 APs
- It defines the minimum interoperability and capability requirements that certified devices must meet (Correct answer)
- It provides RSSI thresholds for Wi-Fi 7 deployments
- It replaces the IEEE 802.11be standard
Correct answer: It defines the minimum interoperability and capability requirements that certified devices must meet
Wi-Fi Alliance certification requirements define the minimum interoperability criteria, helping architects predict consistent cross-vendor behavior in multi-vendor deployments.
Question 5: A site survey reveals that measured SNR values are consistently 8 dB lower than predicted. What is the most evidence-based next step?
- Increase AP transmit power to compensate immediately
- Investigate RF absorption and reflection factors (materials, obstacles) not modeled in the predictive tool and update the model (Correct answer)
- Accept the discrepancy and proceed with the deployment
- Replace the spectrum analyzer and re-survey
Correct answer: Investigate RF absorption and reflection factors (materials, obstacles) not modeled in the predictive tool and update the model
A systematic gap between predicted and measured SNR indicates the predictive model is missing environmental factors that must be identified and corrected before deployment.
Question 6: Which combination of data sources provides the strongest evidence base for a comprehensive wireless capacity planning report?
- Vendor capacity calculators alone
- Client density counts, per-client application bandwidth requirements, airtime utilization measurements, and RSSI coverage data (Correct answer)
- End-user device count from the help desk ticketing system
- AP count and floor plan dimensions
Correct answer: Client density counts, per-client application bandwidth requirements, airtime utilization measurements, and RSSI coverage data
Combining client density, application bandwidth needs, airtime utilization, and RSSI data addresses all capacity planning dimensions with objective, measured inputs.
Question 7: After deploying WPA3-Enterprise, a security team wants evidence that PMF (Protected Management Frames) is active for all clients. Which method provides direct verification?
- Confirm PMF is set to required in the AP configuration
- Capture 802.11 frames and verify management frames include MIC fields, confirming PMF negotiation (Correct answer)
- Check that clients show WPA3 in their connection properties
- Run a ping test to confirm network connectivity
Correct answer: Capture 802.11 frames and verify management frames include MIC fields, confirming PMF negotiation
Capturing frames and verifying the presence of MIC fields in management frames provides direct protocol-level evidence that PMF is actively protecting the management channel.
CWNA Research & Evidence-Based Practice 5
A CWNA professional is asked to prove that a recent firmware update improved network performance.
Which research practice ensures a valid conclusion?