CWNA Research & Evidence-Based Practice 2 — Questions and Answers
Question 1: A wireless engineer wants to validate throughput claims made by a vendor for an 802.11ax AP. Which methodology provides the most evidence-based comparison?
- Accept vendor datasheets as authoritative
- Conduct controlled lab tests using RFC 2544 or similar reproducible benchmarks (Correct answer)
- Ask peers on forums for their experience
- Check the AP's marketing brochure for real-world figures
Correct answer: Conduct controlled lab tests using RFC 2544 or similar reproducible benchmarks
RFC 2544 and similar standardized benchmarks provide reproducible, controlled conditions that allow objective comparison of vendor claims.
Question 2: When reviewing a site survey report, which data source best supports evidence-based conclusions about channel utilization?
- Visual inspection of the physical environment
- Spectrum analyzer captures taken at multiple locations and times (Correct answer)
- End-user complaints about slow performance
- Vendor recommended channel plans
Correct answer: Spectrum analyzer captures taken at multiple locations and times
Spectrum analyzer captures provide objective, quantitative RF data that directly measures channel utilization across the environment.
Question 3: A CWNA candidate reads an IEEE 802.11 amendment. What is the primary purpose of referencing the IEEE standard rather than a third-party summary?
- IEEE documents are shorter and easier to read
- Third-party summaries are always inaccurate
- IEEE standards are the authoritative technical specification and prevent misinterpretation (Correct answer)
- IEEE documents include product recommendations
Correct answer: IEEE standards are the authoritative technical specification and prevent misinterpretation
IEEE 802.11 standards are the definitive technical specifications, ensuring that design and troubleshooting decisions are based on accurate, primary-source information.
Question 4: Which metric, collected during a predictive site survey, should be validated with a physical (passive) survey to ensure evidence-based deployment?
- AP model number
- Estimated RSSI coverage contours (Correct answer)
- Number of SSIDs configured
- DHCP lease duration
Correct answer: Estimated RSSI coverage contours
Predictive surveys use modeled RSSI estimates that must be validated with real-world passive survey measurements to confirm actual RF propagation.
Question 5: A wireless team uses historical packet captures to investigate a recurring authentication failure. This approach best represents which research practice?
- Anecdotal evidence gathering
- Evidence-based root-cause analysis using primary data artifacts (Correct answer)
- Vendor escalation without local investigation
- Guessing based on common failure patterns
Correct answer: Evidence-based root-cause analysis using primary data artifacts
Packet captures are primary data artifacts that allow systematic, evidence-based analysis of authentication exchange failures.
Question 6: When comparing two 802.11ac APs in a production environment, what practice ensures results are scientifically valid?
- Test each AP at different times of day in different buildings
- Hold all variables constant except the AP model being tested (Correct answer)
- Use only vendor-provided performance scores
- Test during peak hours only to maximize traffic load
Correct answer: Hold all variables constant except the AP model being tested
Controlling all variables except the one being tested (the AP model) is the fundamental principle of controlled experimentation.
Question 7: A network administrator wants to apply evidence-based practices to reduce co-channel interference. Which action best reflects this approach?
- Increase transmit power on all APs without measurement
- Deploy a non-overlapping channel plan verified by post-deployment spectrum analysis (Correct answer)
- Trust the automatic channel selection feature without review
- Reduce the number of SSIDs based on user opinion
Correct answer: Deploy a non-overlapping channel plan verified by post-deployment spectrum analysis
Designing a non-overlapping channel plan and confirming it with spectrum analysis ensures the interference reduction is validated by objective data.
CWNA Research & Evidence-Based Practice 2
A wireless engineer wants to validate throughput claims made by a vendor for an 802.11ax AP.
Which methodology provides the most evidence-based comparison?