CompTIA Network+ (N10-009)Network ImplementationHard
A wireless engineer configures access points in a dense multi-AP office deployment to use an 80MHz channel width in the 5GHz band to maximize per-client throughput. Users soon report intermittent connectivity issues and slow speeds near AP boundaries. What is the most likely cause of this problem?
- A80MHz channels are incompatible with WPA3 encryption
- B80MHz channel width disables DFS channel avoidance entirely
- C80MHz channels can only be used with 2.4GHz radios, causing a band mismatch
- DWider channels reduce the number of non-overlapping channels, increasing co-channel interference between nearby APs
Show answer & explanationAnswer & explanation
Correct answer: D. Wider channels reduce the number of non-overlapping channels, increasing co-channel interference between nearby APs
Bonding channels into wider 80MHz blocks consumes more of the available 5GHz spectrum, leaving fewer non-overlapping channels for neighboring APs to use, which increases the likelihood of co-channel interference and degraded performance in dense deployments.
Why the other options are wrong
- A. Channel width and WPA3 encryption are independent; there is no such incompatibility.
- B. Channel bonding does not disable DFS; DFS operation depends on the specific UNII band used, not channel width.
- C. 80MHz channel bonding is a 5GHz feature; 2.4GHz does not typically support such wide channels due to limited spectrum.
Channel Bonding Trade-off
Combining multiple 20MHz channels (e.g., into 40/80/160MHz) increases per-client throughput but reduces the number of non-overlapping channels available, raising the risk of co-channel interference in dense AP deployments.
- 80MHz channel = four bonded 20MHz channels
- Fewer available channels means more APs must reuse the same frequency
- Trade-off: higher speed vs. more interference in dense environments
Memory trick: Wider highway lanes = fewer total roads to share.