N10-009 Network Troubleshooting Practice Question
A user reports intermittent connectivity issues. The technician notices that the link lights on both the PC and the switch are solid, but the user experiences periodic drops. The technician runs a cable test and finds that one pair of wires is open. Which standard is the cable likely violating?
⚠ Common exam trap
The trap here is that candidates see 'link lights solid' and assume the cable is fully functional, but solid link lights only indicate that at least one pair (or the necessary pairs for the negotiated speed) is electrically connected, not that all pairs meet the TIA/EIA-568 standard for the expected speed.
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
✓
TIA/EIA-568
The TIA/EIA-568 standard specifies the wiring pinouts and performance requirements for twisted-pair cabling, including that all four pairs must be properly terminated and continuous. An open pair violates this standard because it breaks the required electrical continuity, leading to signal degradation and intermittent connectivity. The solid link lights indicate basic electrical connectivity on some pairs, but the open pair causes periodic drops when the network attempts to use that pair for data transmission.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
TIA/EIA-568
Why this is correct
TIA/EIA-568 is the definitive standard for structured cabling in commercial buildings, specifying the wiring schemes like T568A and T568B for twisted-pair cables. An "open pair" directly violates these precise pinout requirements, preventing proper signal transmission and causing the reported intermittent connectivity issues. Adherence to this standard ensures reliable physical layer communication and simplifies troubleshooting of cabling faults.
- ✗
IEEE 802.3
Why it's wrong here
IEEE 802.3 defines the Ethernet standard, encompassing various physical layer implementations and data link layer specifications for wired networks. While it dictates how data is transmitted over the physical medium and specifies signaling, it defers the precise physical wiring configurations, including pinouts and termination practices, to other standards like TIA/EIA-568. An "open pair" is a physical wiring defect, not an Ethernet protocol or signaling issue defined by 802.3 itself.
When this WOULD be correct
A question asking which standard defines Ethernet frame formats, MAC addresses, or CSMA/CD access method would have IEEE 802.3 as the correct answer. For example: 'Which standard specifies the maximum frame size for Ethernet?'
- ✗
ISO 9001
Why it's wrong here
ISO 9001 is an international standard focused on quality management systems, designed to help organizations meet customer and regulatory requirements consistently. It establishes criteria for a quality management system but does not dictate technical specifications for network cabling, such as pinouts or physical layer characteristics. Therefore, it is irrelevant to diagnosing a specific cabling fault like an open pair causing intermittent connectivity.
When this WOULD be correct
A question asking which standard applies to a company's quality management system for network cable installation processes, where the correct answer is ISO 9001 because it governs quality assurance procedures.
- ✗
RFC 1918
Why it's wrong here
RFC 1918 is a Request for Comments document that reserves specific IP address ranges for use in private networks, preventing their routing on the public internet. This standard operates at the network layer (Layer 3) of the OSI model, addressing logical addressing schemes. It has no bearing on physical layer issues such as cable integrity, pinouts, or the diagnosis of an "open pair" causing intermittent connectivity.
When this WOULD be correct
A question about a user unable to access the internet from a private IP address, where the router is not performing NAT correctly. The correct answer would be RFC 1918 because the issue involves private address space.
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.
✓TIA/EIA-568Correct answer▾
Why this is correct
TIA/EIA-568 is the definitive standard for structured cabling in commercial buildings, specifying the wiring schemes like T568A and T568B for twisted-pair cables. An "open pair" directly violates these precise pinout requirements, preventing proper signal transmission and causing the reported intermittent connectivity issues. Adherence to this standard ensures reliable physical layer communication and simplifies troubleshooting of cabling faults.
✗IEEE 802.3Wrong answer — click to see why▾
Why this is wrong here
IEEE 802.3 defines Ethernet standards for physical and data link layers, but it does not specify cabling pinouts or pair configurations. An open pair violating wiring standards is a cabling issue, not a protocol issue.
★ When this WOULD be the correct answer
A question asking which standard defines Ethernet frame formats, MAC addresses, or CSMA/CD access method would have IEEE 802.3 as the correct answer. For example: 'Which standard specifies the maximum frame size for Ethernet?'
Why candidates choose this
Candidates may confuse IEEE 802.3 with cabling standards because both relate to networking hardware, or they may think any network issue falls under IEEE standards.
✗ISO 9001Wrong answer — click to see why▾
Why this is wrong here
ISO 9001 is a quality management standard, not a cabling or networking standard. An open wire pair violates TIA/EIA-568 cabling specifications, not ISO 9001.
★ When this WOULD be the correct answer
A question asking which standard applies to a company's quality management system for network cable installation processes, where the correct answer is ISO 9001 because it governs quality assurance procedures.
Why candidates choose this
Candidates may confuse ISO 9001 with a technical standard due to its broad recognition, or mistakenly think it covers physical cabling requirements.
✗RFC 1918Wrong answer — click to see why▾
Why this is wrong here
RFC 1918 defines private IP address ranges (e.g., 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) and is unrelated to cabling standards or physical layer issues like an open wire pair.
★ When this WOULD be the correct answer
A question about a user unable to access the internet from a private IP address, where the router is not performing NAT correctly. The correct answer would be RFC 1918 because the issue involves private address space.
Why candidates choose this
Candidates may confuse RFC 1918 with a general networking standard, or think it covers physical cabling due to its association with network setup, but it only addresses IP addressing.
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
About these practice questions
This N10-009 question is part of Courseiva's 464-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam 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.