N10-009 Question 158
Single answer2.3 Given a scenario, select and configure wireless devices and technologies.A network administrator is upgrading wireless coverage in a crowded office that occupies one floor of a downtown building. Employees report slow connections and frequent retransmissions during business hours, especially in conference rooms near neighboring tenants. A site survey shows heavy channel overlap and interference on the 2.4 GHz band. Most company laptops and phones support dual-band Wi-Fi. The administrator wants to improve performance without replacing every client device. Which action is the BEST choice?
- A
Configure the access points to prefer 5 GHz operation and use non-overlapping 5 GHz channels where possible
- B
Increase transmit power on all 2.4 GHz radios so users can maintain stronger signal levels throughout the floor
- C
Set all access points to the same 2.4 GHz channel so clients can roam more easily between conference rooms
- D
Disable WPA2/WPA3 security temporarily to reduce management overhead and improve throughput
Show answer and explanation
Correct answer: A
Explanation
The best answer is to move as much client traffic as possible to 5 GHz and apply proper channel planning there. In crowded office environments, the 2.4 GHz band is frequently saturated because it has fewer non-overlapping channels and is shared with many other devices. Since most client devices in the scenario are dual-band, band steering or equivalent configuration to prefer 5 GHz is a practical and standards-aligned approach. Industry best practices from enterprise wireless design guidance consistently recommend minimizing reliance on 2.4 GHz in high-density deployments and using careful RF planning to reduce co-channel and adjacent-channel interference. This question tests the ability to select and configure wireless technologies based on a site survey rather than relying on simplistic fixes such as increasing power or weakening security.
- A. Correct.
Correct. In a high-density environment with documented 2.4 GHz interference, steering capable devices toward 5 GHz is the best practical improvement. The 5 GHz band typically offers more available channels, less interference from common consumer devices, and less co-channel overlap than 2.4 GHz. Using non-overlapping 5 GHz channels where possible aligns with wireless design best practices for office deployments and improves throughput and airtime efficiency without requiring replacement of dual-band clients.
- B. Incorrect.
Incorrect. Increasing transmit power on 2.4 GHz radios often makes contention and interference worse in dense environments. While stronger signal may seem helpful, it can enlarge the cell size, increase co-channel interference, and cause clients to stay associated with distant APs longer than they should. This does not solve the root problem of spectrum congestion and overlap.
- C. Incorrect.
Incorrect. Putting all APs on the same 2.4 GHz channel generally increases co-channel interference and reduces capacity. Roaming is not achieved by using the same channel everywhere; it depends on client behavior, SSID/security consistency, and proper RF design. In 2.4 GHz, the standard practice is to use non-overlapping channels such as 1, 6, and 11 where applicable, not one shared channel across the entire floor.
- D. Incorrect.
Incorrect. Disabling WPA2/WPA3 is not an acceptable performance optimization. It creates a major security risk and does not address RF interference or channel overlap. Modern wireless performance issues in dense deployments are far more often related to airtime contention, channel planning, and band utilization than encryption overhead.