N10-009 Network Troubleshooting Practice Question
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?
⚠ Common exam trap
Many 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.
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
✓
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.
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
Signal attenuation refers to the reduction in signal strength as it travels through a medium or encounters obstacles. While metal objects can contribute to attenuation by absorbing or blocking RF energy, the scenario explicitly states that signal strength remains high. Therefore, simple signal attenuation, which would manifest as a weak signal, is not the primary cause of the reported connectivity issues in this specific context.
When this WOULD be correct
A question where users report low signal strength or complete loss of connectivity when moving behind large metal objects, such as in a factory with thick concrete walls or metal enclosures, would make signal attenuation the correct answer.
- ✓
Multipath interference
Why this is correct
Metal racks in a warehouse environment are highly reflective surfaces for radio frequency (RF) signals, causing the wireless signal to travel multiple paths to reach the receiver. These reflected signals arrive at slightly different times and phases, interfering with the direct signal. This multipath interference leads to signal cancellation or distortion, resulting in high perceived signal strength but corrupted data and poor throughput. Users experience connectivity loss even when their devices report strong signal.
- ✗
Co-channel interference
Why it's wrong here
Co-channel interference occurs when multiple wireless access points or devices operate on the same frequency channel within overlapping coverage areas. This causes competing transmissions to corrupt each other, leading to reduced throughput and dropped connections. While it degrades wireless performance, co-channel interference is typically a result of poor channel planning or external rogue devices, not a direct consequence of metal structures reflecting signals in a way that causes this specific type of interference.
When this WOULD be correct
A question where users in a high-density office experience intermittent connectivity and low throughput despite strong signal, and multiple APs are on the same channel due to poor planning. The correct answer would be co-channel interference.
- ✗
Insufficient DHCP scope
Why it's wrong here
Insufficient DHCP scope means the network's DHCP server has run out of available IP addresses to assign to client devices. This issue would prevent new devices from obtaining an IP address or existing devices from renewing their leases, leading to a complete inability to join the network. However, this is a logical network configuration problem that would affect devices regardless of their physical location near metal objects, and it doesn't explain sudden connectivity loss for already connected devices.
When this WOULD be correct
A question where users cannot connect to the network at all, or new devices fail to get an IP address, and the DHCP server shows no available addresses in the pool. For example: 'Users report that after adding 50 new devices, some cannot obtain an IP address. What is the most likely cause?'
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.
✓Multipath interferenceCorrect answer▾
Why this is correct
Metal racks in a warehouse environment are highly reflective surfaces for radio frequency (RF) signals, causing the wireless signal to travel multiple paths to reach the receiver. These reflected signals arrive at slightly different times and phases, interfering with the direct signal. This multipath interference leads to signal cancellation or distortion, resulting in high perceived signal strength but corrupted data and poor throughput. Users experience connectivity loss even when their devices report strong signal.
✗Signal attenuationWrong answer — click to see why▾
Why this is wrong here
Signal attenuation refers to the reduction of signal strength over distance or through obstacles. In this scenario, signal strength remains high, so attenuation is not the cause; the issue is multipath interference caused by reflections off the metal racks.
★ When this WOULD be the correct answer
A question where users report low signal strength or complete loss of connectivity when moving behind large metal objects, such as in a factory with thick concrete walls or metal enclosures, would make signal attenuation the correct answer.
Why candidates choose this
Candidates may associate metal racks with blocking signals, leading them to think of attenuation, but they overlook that the signal strength is still high, which points to multipath rather than attenuation.
✗Co-channel interferenceWrong answer — click to see why▾
Why this is wrong here
Co-channel interference occurs when multiple access points use the same frequency channel, causing contention. The described issue is localized near metal racks, not due to overlapping channels, and signal strength remains high, ruling out co-channel interference.
★ When this WOULD be the correct answer
A question where users in a high-density office experience intermittent connectivity and low throughput despite strong signal, and multiple APs are on the same channel due to poor planning. The correct answer would be co-channel interference.
Why candidates choose this
Candidates may confuse any wireless performance issue with interference, and 'co-channel interference' is a common cause of throughput drops, leading them to select it without considering the specific effect of metal racks causing multipath.
✗Insufficient DHCP scopeWrong answer — click to see why▾
Why this is wrong here
Insufficient DHCP scope would cause devices to fail to obtain an IP address, not cause high signal strength with low throughput. The issue here is interference from metal racks, not IP address exhaustion.
★ When this WOULD be the correct answer
A question where users cannot connect to the network at all, or new devices fail to get an IP address, and the DHCP server shows no available addresses in the pool. For example: 'Users report that after adding 50 new devices, some cannot obtain an IP address. What is the most likely cause?'
Why candidates choose this
Candidates may think that connectivity loss implies an IP address issue, confusing 'loss of connectivity' with 'inability to connect' due to DHCP exhaustion.
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?”
Quick reference
Access Control Model Comparison
| Model | Acronym | Who Controls Access? | Best For |
|---|---|---|---|
| Discretionary Access Control | DAC | Resource owner | Small teams, file shares |
| Mandatory Access Control | MAC | System / security labels | Classified govt / military |
| Role-Based Access Control | RBAC | Administrator (via roles) | Enterprise environments |
| Attribute-Based Access Control | ABAC | Policy engine (user + resource attributes) | Fine-grained, dynamic policies |
| Rule-Based Access Control | RuBAC | System rules / ACLs | Firewall rules, network ACLs |
Go deeper
Related to this question
Learn chapter
Troubleshoot: Cable and Physical Layer
Key term
RSSI
RSSI is a measurement of the power level in a received radio signal, used by wireless devices to gauge signal strength.
Key term
Receiver
A receiver is a hardware device or software component that accepts incoming signals, data, or transmissions from a sender over a communication channel.
About these practice questions
Courseiva writes every N10-009 question from scratch — 464 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. 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.