220-1101 Question 74
Single answerFrequenciesA technician is troubleshooting slow and inconsistent Wi-Fi performance in a small office. Employees report that laptops near the break room microwave lose connectivity briefly when lunch is being heated, while conference room devices farther away from the access point have weak signal but stay connected. The current wireless network uses a single 2.4 GHz SSID. Which action is the BEST way to reduce the microwave-related interference while also improving performance for nearby modern laptops?
- A
Move nearby users to a 5 GHz SSID and leave older devices on 2.4 GHz
- B
Change the 2.4 GHz channel from 6 to 11 and keep all devices on the same SSID
- C
Lower the access point transmit power so the microwave has less effect on the signal
- D
Replace the wireless NICs in all laptops with Bluetooth adapters
Show answer and explanation
Correct answer: A
Explanation
The best answer is to move compatible devices to 5 GHz. In A+ Core 1, candidates are expected to understand that 2.4 GHz offers longer range but is more prone to interference from devices such as microwaves, cordless phones, and Bluetooth equipment. By contrast, 5 GHz provides higher throughput and experiences less interference in typical office environments, though with shorter range. The scenario also distinguishes between two separate wireless issues: interference near the microwave and weaker signal farther from the access point. The question asks for the BEST action to reduce microwave-related interference while improving performance for nearby modern laptops, which is why 5 GHz is the most appropriate choice. This aligns with common wireless networking best practices documented by enterprise WLAN vendors and standard troubleshooting guidance for RF interference.
- A. Correct.
Correct. Microwave ovens commonly interfere with the 2.4 GHz band because they operate around the same frequency range. Moving capable devices to 5 GHz avoids that interference and typically improves throughput for nearby modern laptops because 5 GHz generally supports higher data rates and has more available channels. Keeping older devices on 2.4 GHz is a practical real-world solution in mixed-device environments.
- B. Incorrect.
Incorrect. Changing from channel 6 to 11 may help if the problem is overlapping Wi-Fi channel congestion, but it does not address the root issue of microwave interference affecting the entire 2.4 GHz band. The symptoms specifically occur when the microwave is in use, which points to frequency-band interference rather than just a poor channel choice.
- C. Incorrect.
Incorrect. Lowering transmit power usually reduces coverage area and can make signal problems worse, especially for devices farther from the access point. It does not meaningfully prevent microwave interference, which is external RF noise in the 2.4 GHz range.
- D. Incorrect.
Incorrect. Bluetooth also uses the 2.4 GHz spectrum, so it would not solve the interference problem. In addition, Bluetooth is not a replacement for standard office Wi-Fi networking for laptops needing normal LAN and internet access.