CWS Research Methods & Evidence-Based Practice 3

Question 1

During a wireless network assessment, you collect throughput data at 30 locations. The results are heavily skewed by three locations with unusually low values. Which measure of central tendency BEST represents typical network performance?

Accepted Answer

Median

Answer

The median is resistant to outliers, making it the best representation of typical performance when extreme low values skew the distribution.

Question 2

An engineer performs both passive and active surveys at the same location. The passive survey shows strong RSSI, but the active survey reveals low throughput. What is the MOST likely explanation?

Accepted Answer

Hidden node interference or high retry rates are degrading actual link performance

Answer

Strong RSSI with poor throughput typically indicates MAC-layer issues like excessive retries caused by hidden nodes or high interference, not physical signal weakness.

Question 3

When using iPerf3 to benchmark wireless throughput, running the test in which direction provides the MOST insight into uplink performance for VoIP quality assessment?

Accepted Answer

Client to server (uplink)

Answer

For VoIP, uplink performance is critical because voice from the client to the server must be assessed; running iPerf3 client-to-server measures this direction.

Question 4

A wireless engineer finds that channel utilization consistently exceeds 70% in a high-density auditorium. What evidence-based design change is MOST appropriate?

Accepted Answer

Add APs on non-overlapping channels to distribute the load

Answer

Adding APs on non-overlapping channels distributes client load and reduces per-AP utilization, which is the evidence-based solution for channel saturation.

Question 5

Which protocol capture filter would BEST isolate 802.11 management frames to analyze roaming behavior in a Wireshark capture?

Accepted Answer

wlan.fc.type == 0

Answer

In 802.11, frame type 0 designates management frames, which include probe requests/responses, association, and authentication frames used during roaming.

(CWS) Certified Wireless Specialist Practice Test

(CWS) Certified Wireless Specialist Practice Test

CWS Research Methods & Evidence-Based Practice 3