The answer is co-channel interference, the most likely cause of slow and dropping connections when multiple access points in the vicinity all use channel 6. This occurs because overlapping basic service sets on the same channel force devices to share airtime through CSMA/CA, leading to contention, increased collisions, and reduced throughput even with adequate signal strength. On the CompTIA Network+ N10-009 exam, this scenario tests your understanding of 802.11 wireless coexistence and the difference between co-channel interference and adjacent-channel interference—a common trap where test-takers blame weak signals instead of channel overlap. Remember the memory tip: “Same channel, same pain; different channel, less strain.”
N10-009 Network Troubleshooting Practice Question
This N10-009 practice question tests your understanding of network troubleshooting. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
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?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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
The correct answer is B because 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.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
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.
✓
Co-channel interference
Why this is correct
Multiple APs on the same channel overlap, causing contention and retransmissions, which reduces throughput.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
Incorrect SSID configured
Why it's wrong here
An incorrect SSID would prevent clients from seeing the network at all.
✗
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.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume signal strength is the only factor for wireless performance, but Cisco 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.
Detailed technical explanation
How to think about this question
Co-channel interference occurs when multiple access points on the same 802.11 channel are within range of each other, causing them to share the same half-duplex medium. The CSMA/CA protocol forces each BSS to defer transmissions when the channel is busy, leading to increased backoff times and retransmissions. In the 2.4 GHz band, only three non-overlapping channels (1, 6, 11) exist, so overlapping channels like three APs on channel 6 is a common real-world misconfiguration that severely degrades performance.
KKey Concepts to Remember
Read the scenario before looking for a memorised answer.
Find the constraint that changes the correct option.
Eliminate answers that are true in general but not in this case.
TExam Day Tips
→Watch for words such as best, first, most likely and least administrative effort.
→Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the N10-009 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this N10-009 question in full detail.
Network Troubleshooting — This question tests Network Troubleshooting — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Co-channel interference — The correct answer is B because 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.
What should I do if I get this N10-009 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.