CWNA Case Studies & Practical Application 3 — Questions and Answers
Question 1: An outdoor stadium deploys Wi-Fi for fan engagement. Coverage maps show good RSSI but users report slow speeds during games. What is the MOST likely cause?
- The APs are too far from the core switch
- Airtime is being consumed by high client density causing contention (Correct answer)
- The stadium's concrete walls are reflecting 5 GHz signals
- DHCP scope exhaustion is preventing new associations
Correct answer: Airtime is being consumed by high client density causing contention
In high-density environments, even strong RSSI does not prevent airtime contention when thousands of clients compete for channel access simultaneously.
Question 2: A logistics company installs WLAN in a metal-shelved warehouse. After installation, large dead zones are found in aisles. The site survey was done without shelves installed. What is the ROOT CAUSE?
- The APs were configured with the wrong SSID
- Metal shelving causes multipath and signal absorption not captured in the pre-deployment survey (Correct answer)
- The DHCP server is out of IP addresses
- Band steering is redirecting clients to 2.4 GHz
Correct answer: Metal shelving causes multipath and signal absorption not captured in the pre-deployment survey
Metal shelving significantly attenuates and reflects RF signals; a survey performed before fixtures are in place fails to capture the real post-deployment RF environment.
Question 3: A coffee shop owner wants to provide guest Wi-Fi while protecting the POS system on the same AP. Which configuration BEST achieves this?
- Use the same SSID with MAC filtering to block guest devices from POS
- Configure separate SSIDs mapped to separate VLANs with firewall rules between them (Correct answer)
- Enable WEP on the guest SSID to limit access
- Assign static IPs to POS devices and DHCP to guest devices on the same network
Correct answer: Configure separate SSIDs mapped to separate VLANs with firewall rules between them
VLAN segmentation with firewall policies between VLANs isolates guest traffic from the POS network while allowing both to share the same physical AP infrastructure.
Question 4: During a WLAN audit, you discover clients are associating to an SSID that matches your corporate network but originates from an unknown device. What type of attack is this?
- Deauthentication flood attack
- Evil twin (honeypot) AP attack (Correct answer)
- KRACK (Key Reinstallation Attack)
- Beacon stuffing attack
Correct answer: Evil twin (honeypot) AP attack
An evil twin attack involves a rogue AP broadcasting a legitimate-looking SSID to lure clients into associating with it, enabling credential theft or traffic interception.
Question 5: A hotel deploys Wi-Fi with per-room coverage using APs in hallways. Guests in corner rooms report weak signal. Which antenna type would BEST improve coverage into corner rooms?
- High-gain omnidirectional antennas to maximize range in all directions
- Patch antennas aimed toward corner rooms from hallway APs (Correct answer)
- Yagi antennas pointed toward the elevator core
- Dipole antennas mounted horizontally on the ceiling
Correct answer: Patch antennas aimed toward corner rooms from hallway APs
Patch antennas provide directional gain and can be aimed precisely at corner rooms where omnidirectional coverage from hallway APs is weakest.
Question 6: A company's security team reports that client devices are being disconnected from the WLAN without their consent. A packet capture shows repeated deauthentication frames. What security feature would PREVENT this attack?
- WPA3-SAE replacing WPA2-PSK
- 802.11w Management Frame Protection (PMF) (Correct answer)
- RADIUS authentication with EAP-TLS
- Enabling band steering on all APs
Correct answer: 802.11w Management Frame Protection (PMF)
802.11w (PMF) encrypts and authenticates management frames including deauthentication frames, preventing spoofed deauth attacks.
Question 7: A manufacturing plant needs WLAN for barcode scanners that use legacy 802.11b/g. The new APs support 802.11ax. What configuration concern should be addressed to maintain backward compatibility without hurting modern client performance?
- Disable 5 GHz radios so legacy clients can connect
- Set minimum basic rates to 11 Mbps to drop legacy 802.11b rates but keep legacy clients on 2.4 GHz (Correct answer)
- Enable 802.11b support on 5 GHz radio for scanner compatibility
- Disable OFDMA to prevent interference with legacy DSSS devices
Correct answer: Set minimum basic rates to 11 Mbps to drop legacy 802.11b rates but keep legacy clients on 2.4 GHz
Raising the minimum basic rate to 11 Mbps removes 1, 2, and 5.5 Mbps 802.11b rates, reducing overhead while keeping 802.11g-capable scanners functional on 2.4 GHz.
CWNA Case Studies & Practical Application 3
An outdoor stadium deploys Wi-Fi for fan engagement.
Coverage maps show good RSSI but users report slow speeds during games.
What is the MOST likely cause?