CWDP Wireless Network Troubleshooting

Question 1

What is the most common cause of sticky client behavior in enterprise WLANs?

Accepted Answer

Clients maintaining association with a distant AP instead of roaming to a closer one

Answer

Sticky clients occur when devices maintain their connection to the original AP even after moving to an area better served by another AP, often due to the client's roaming algorithm threshold being too conservative.

Question 2

How can excessive co-channel interference (CCI) be identified during troubleshooting?

Accepted Answer

High retry rates and low throughput despite strong signal levels

Answer

CCI manifests as high retry/retransmission rates and degraded throughput even when clients show strong received signal strength, because multiple APs on the same channel contend for airtime.

Question 3

What tool is best suited for identifying non-Wi-Fi interference sources?

Accepted Answer

Spectrum analyzer

Answer

A spectrum analyzer shows all RF energy in the frequency band, including non-Wi-Fi sources like microwave ovens, Bluetooth devices, cordless phones, and video bridges that a Wi-Fi scanner cannot detect.

Question 4

What does a high percentage of management frames indicate in a wireless packet capture?

Accepted Answer

Possible network instability with frequent client associations, disassociations, or probe requests

Answer

A disproportionately high percentage of management frames (probe requests, authentication, association, deauthentication) suggests clients are struggling to connect or stay connected, indicating network instability.

Question 5

What is the recommended approach when users report intermittent connectivity issues?

Accepted Answer

Correlate the timing with potential interference sources, check client roaming behavior, and verify AP health

Answer

Intermittent issues require systematic investigation: correlating occurrence times with potential interference (shift schedules, equipment usage), analyzing client roaming logs, checking AP resource utilization, and reviewing environmental changes.

Certified Wireless Design Professional (CWDP) Practice Test

Certified Wireless Design Professional (CWDP) Practice Test

CWDP Wireless Network Troubleshooting