220-1101 Question 73
Single answer2.2 Explain wireless networking technologies.A technician is troubleshooting Wi-Fi performance in a small office. Users report that laptops connected to the company's 2.4 GHz SSID frequently lose speed around lunchtime, while a newer 5 GHz SSID remains stable but does not reach a conference room at the far end of the building. The wireless router is functioning normally. Which action should the technician take FIRST to improve the 2.4 GHz network performance without reducing overall coverage?
- A
Change the 2.4 GHz network to a less congested non-overlapping channel such as 1, 6, or 11
- B
Disable the 2.4 GHz radio and require all devices to use only the 5 GHz SSID
- C
Increase the 5 GHz transmit power so it has the same wall penetration as 2.4 GHz
- D
Move the 2.4 GHz network to channel 4 to avoid overlap with nearby networks
Show answer and explanation
Correct answer: A
Explanation
This question tests practical understanding of wireless networking technologies in a real support scenario. The 2.4 GHz band offers better range and obstacle penetration than 5 GHz, but it is more susceptible to congestion and interference from neighboring WLANs and common devices. In most standard 2.4 GHz Wi-Fi deployments, technicians should use non-overlapping channels 1, 6, and 11 to minimize adjacent-channel interference. By contrast, 5 GHz usually provides higher throughput and more available channels, but with shorter effective range. A CompTIA A+ candidate should recognize that the first step for a crowded 2.4 GHz network is channel optimization rather than disabling the band or assuming transmit power changes will overcome frequency limitations. This aligns with common WLAN troubleshooting best practices documented by enterprise wireless vendors and general IEEE 802.11 deployment guidance.
- A. Correct.
Correct. In the 2.4 GHz band, interference and channel overlap are common causes of poor performance, especially in busy office environments around peak usage times. Best practice is to use non-overlapping channels 1, 6, or 11 in regions where those channels apply. Changing to the least congested of these channels is a practical first troubleshooting step that can improve throughput and stability while keeping the longer range and better wall penetration of 2.4 GHz.
- B. Incorrect.
Incorrect. Disabling 2.4 GHz would likely reduce coverage because 5 GHz generally has shorter range and less ability to penetrate walls and obstacles. The scenario specifically says the 5 GHz SSID does not reach the conference room well, so forcing all clients to 5 GHz would create a coverage problem rather than solving the original issue.
- C. Incorrect.
Incorrect. Although adjusting transmit power can sometimes help with coverage boundaries, it does not make 5 GHz behave like 2.4 GHz in terms of propagation characteristics. Higher-frequency 5 GHz signals still typically have less range and poorer penetration through walls than 2.4 GHz. Also, the immediate issue is lunchtime slowdown on 2.4 GHz, which points more directly to interference or congestion.
- D. Incorrect.
Incorrect. Channel 4 overlaps significantly with adjacent 2.4 GHz channels and is not considered a best-practice choice in typical 20 MHz deployments. A common misconception is that any different channel reduces interference, but in 2.4 GHz, overlapping channels can worsen contention and performance.