The answer is multipath interference. This occurs when wireless signals reflect off large metal racks in the warehouse, causing multiple delayed copies of the signal to arrive at the tablet’s receiver. These out-of-phase copies cancel parts of the original signal, a phenomenon known as phase cancellation, which corrupts the data and forces the 802.11 MAC layer to retransmit frames repeatedly. The result is a drastic drop in throughput even though the received signal strength indicator (RSSI) remains high—a classic symptom that tricks many test-takers into thinking the issue is range or absorption. On the CompTIA Network+ N10-009 exam, this scenario tests your understanding of how physical environment factors like reflective surfaces degrade performance without weakening signal strength. A common trap is to blame interference from other access points or channel congestion, but the key clue is the combination of high signal and low throughput near metal. Remember the mnemonic: “High bars, slow cars—think multipath scars.”
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 warehouse report that their wireless tablets lose connectivity when moving near large metal racks. The signal strength remains high but throughput drops significantly. 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.
Why wrong: Attenuation reduces signal strength, but the scenario states signal strength remains high, so attenuation is not the culprit.
B
Multipath interference
Metal racks cause signal reflections, creating multiple signal paths that interfere with each other, resulting in high signal strength but poor throughput.
C
Co-channel interference
Why wrong: Co-channel interference is caused by other access points or devices operating on the same frequency, not specifically by metal objects.
D
Insufficient DHCP scope
Why wrong: DHCP scope exhaustion would prevent devices from obtaining IP addresses, but the symptom is connectivity loss near metal, not a network-wide issue.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Multipath interference
When wireless signals reflect off large metal surfaces, multiple copies of the signal arrive at the receiver at slightly different times, causing multipath interference. This phase cancellation effect corrupts the signal, forcing the 802.11 MAC layer to retransmit frames, which drastically reduces throughput even though the received signal strength indicator (RSSI) remains high. The metal racks in the warehouse act as reflective surfaces, creating a classic multipath environment.
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.
✗
Signal attenuation
Why it's wrong here
Attenuation reduces signal strength, but the scenario states signal strength remains high, so attenuation is not the culprit.
✓
Multipath interference
Why this is correct
Metal racks cause signal reflections, creating multiple signal paths that interfere with each other, resulting in high signal strength but poor 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.
✗
Co-channel interference
Why it's wrong here
Co-channel interference is caused by other access points or devices operating on the same frequency, not specifically by metal objects.
✗
Insufficient DHCP scope
Why it's wrong here
DHCP scope exhaustion would prevent devices from obtaining IP addresses, but the symptom is connectivity loss near metal, not a network-wide issue.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates confuse high signal strength with good signal quality, not realizing that multipath can cause high RSSI but poor throughput due to phase cancellation and retransmissions.
Trap categories for this question
Scenario analysis trap
Attenuation reduces signal strength, but the scenario states signal strength remains high, so attenuation is not the culprit.
Detailed technical explanation
How to think about this question
Multipath interference is caused by reflections that create multiple propagation paths; the receiver sees a composite signal where delayed copies can cancel or distort the primary signal (destructive interference). This is particularly problematic in 802.11n/ac/ax systems using MIMO and OFDM, where delay spread exceeding the guard interval can cause inter-symbol interference. In real-world warehouse environments, even with high RSSI, the error vector magnitude (EVM) degrades, forcing rate adaptation to lower modulation schemes (e.g., from 64-QAM to QPSK) to maintain link reliability.
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 small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
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: Multipath interference — When wireless signals reflect off large metal surfaces, multiple copies of the signal arrive at the receiver at slightly different times, causing multipath interference. This phase cancellation effect corrupts the signal, forcing the 802.11 MAC layer to retransmit frames, which drastically reduces throughput even though the received signal strength indicator (RSSI) remains high. The metal racks in the warehouse act as reflective surfaces, creating a classic multipath environment.
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.