N10-009 Network Troubleshooting Practice Question
Users in a conference room frequently experience slow and dropping wireless connections. A site survey shows three other access points in the vicinity all using channel 6. Signal strength is adequate. What is the most likely cause?
⚠ Common exam trap
Many candidates assume signal strength is the only factor for wireless performance, but the CompTIA Network+ exam tests the understanding that co-channel interference can cause poor performance even with strong signals, especially when multiple APs share the same channel in a dense environment.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Co-channel interference
All three nearby access points are operating on channel 6, which causes co-channel interference. Even with adequate signal strength, overlapping basic service sets (BSSs) on the same channel lead to contention, increased collisions, and reduced throughput due to the CSMA/CA mechanism in 802.11 networks. This results in slow and dropping connections for users in the conference room.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Incorrect encryption settings
Why it's wrong here
Incorrect encryption would prevent clients from associating or authenticating, not cause intermittent slow performance.
When this WOULD be correct
A question where users cannot connect to a wireless network despite correct SSID and signal, and the network uses WPA2-Enterprise but the client has WPA2-Personal configured, leading to authentication failure.
- ✓
Co-channel interference
Why this is correct
Multiple APs on the same channel overlap, causing contention and retransmissions, which reduces throughput.
- ✗
Incorrect SSID configured
Why it's wrong here
An incorrect SSID would prevent clients from seeing the network at all.
When this WOULD be correct
A question where users cannot see or connect to a wireless network, even though other networks are visible, and a site survey confirms the SSID is not broadcast or is misspelled on the access point.
- ✗
Low antenna gain on the access points
Why it's wrong here
The survey indicated adequate signal strength, so antenna gain is not the issue.
When this WOULD be correct
In a scenario where users experience weak signal or dead spots despite adequate AP coverage, and the site survey shows low RSSI values, low antenna gain on the APs could be the cause. For example, if APs have omnidirectional antennas with 2 dBi gain in a large open area, upgrading to higher-gain antennas (e.g., 5 dBi) might improve coverage.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓Co-channel interferenceCorrect answer▾
Why this is correct
Multiple APs on the same channel overlap, causing contention and retransmissions, which reduces throughput.
✗Incorrect encryption settingsWrong answer — click to see why▾
Why this is wrong here
Incorrect encryption settings would cause authentication failures or inability to connect, not slow or dropping connections with adequate signal strength. The issue is interference from multiple APs on the same channel.
★ When this WOULD be the correct answer
A question where users cannot connect to a wireless network despite correct SSID and signal, and the network uses WPA2-Enterprise but the client has WPA2-Personal configured, leading to authentication failure.
Why candidates choose this
Candidates may confuse connectivity issues with performance issues, thinking encryption mismatches cause intermittent drops, but encryption errors typically result in persistent connection failures.
✗Incorrect SSID configuredWrong answer — click to see why▾
Why this is wrong here
Incorrect SSID configuration would prevent clients from connecting or seeing the network, but the symptoms describe slow and dropping connections with adequate signal strength, which points to interference, not misconfiguration.
★ When this WOULD be the correct answer
A question where users cannot see or connect to a wireless network, even though other networks are visible, and a site survey confirms the SSID is not broadcast or is misspelled on the access point.
Why candidates choose this
Candidates may confuse connectivity issues with configuration errors, assuming that if the network is slow or dropping, the SSID might be misconfigured, but SSID issues typically cause complete inability to connect, not degraded performance.
✗Low antenna gain on the access pointsWrong answer — click to see why▾
Why this is wrong here
Low antenna gain would reduce signal strength, but the site survey indicates adequate signal strength, so antenna gain is not the issue. The problem is interference from multiple APs on the same channel.
★ When this WOULD be the correct answer
In a scenario where users experience weak signal or dead spots despite adequate AP coverage, and the site survey shows low RSSI values, low antenna gain on the APs could be the cause. For example, if APs have omnidirectional antennas with 2 dBi gain in a large open area, upgrading to higher-gain antennas (e.g., 5 dBi) might improve coverage.
Why candidates choose this
Candidates may confuse antenna gain with overall wireless performance, thinking that higher gain always solves connectivity issues, without considering that the problem here is interference, not signal strength.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Go deeper
Related to this question
Learn chapter
Wireless Signal Strength and Coverage Issues
Key term
Received Signal Strength Indicator
Received Signal Strength Indicator (RSSI) is a measurement of how strong a wireless signal is when it reaches a receiving device, like a laptop connecting to Wi-Fi.
Key term
Throughput
Throughput is the rate at which data is successfully transferred from one point to another over a network, typically measured in bits per second.
About these practice questions
One of 472 original N10-009 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This N10-009 practice question is part of Courseiva's free CompTIA certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the N10-009 exam.