Cisco Certified Support Technician (CCST) NetworkingNetwork AccessMedium
A network professional is troubleshooting a slow wireless connection for a user. The user is complaining about frequent disconnections and very low throughput, even when close to the access point. After checking the configuration, it is confirmed that the access point is operating on the 2.4 GHz band and is configured to use channel 6. A wireless survey reveals several other access points in the vicinity also using channel 6. What is the most likely cause of the user's issue?
- AInsufficient transmit power on the access point
- BIncorrect WPA2 password configuration
- CUnsupported 802.11 standard on the user's device
- DChannel interference from neighboring Wi-Fi networks
Show answer & explanationAnswer & explanation
Correct answer: D. Channel interference from neighboring Wi-Fi networks
When multiple wireless access points operate on the same channel in close proximity, they interfere with each other, leading to reduced throughput, increased latency, and frequent disconnections. In the 2.4 GHz band, channels 1, 6, and 11 are non-overlapping.
Why the other options are wrong
- A. Insufficient transmit power would lead to poor signal strength further away, but the user is close to the AP and experiencing issues.
- B. An incorrect WPA2 password would prevent connection entirely, not cause slow speeds and disconnections after connecting.
- C. An unsupported 802.11 standard would likely prevent connection or cause very specific compatibility issues, not general slowness and disconnections when close to the AP.
Wi-Fi Co-channel Interference
Occurs when multiple wireless devices or access points operate on the same frequency channel in overlapping areas, leading to performance degradation.
- Reduces effective throughput and increases latency.
- Especially problematic in the crowded 2.4 GHz band.
- Can be mitigated by using non-overlapping channels (1, 6, 11 in 2.4 GHz).
Memory trick: Too many voices on one channel leads to chaos.