This N10-009 practice question tests your understanding of networking concepts. 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.
A network engineer wants to segment a LAN into multiple broadcast domains without purchasing additional hardware. Which of the following technologies should be implemented?
Subnetting
Why wrong: Subnetting creates broadcast domains but requires a router or Layer 3 switch, not just a switch.
VLANs
VLANs allow a single switch to support multiple broadcast domains, each isolated at Layer 2.
VPN
Why wrong: VPNs provide encrypted tunnels over public networks, not broadcast domain segmentation.
NAT
Why wrong: NAT translates IP addresses but does not segment broadcast domains.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
VLANs
VLANs (Virtual Local Area Networks) allow a network engineer to logically segment a single physical LAN switch into multiple isolated broadcast domains without purchasing additional hardware. By assigning switch ports to different VLAN IDs, broadcast traffic is confined to ports within the same VLAN, effectively creating separate Layer 2 networks on the same switch infrastructure.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Subnetting
Why it's wrong here
Subnetting creates broadcast domains but requires a router or Layer 3 switch, not just a switch.
VLANs
Why this is correct
VLANs allow a single switch to support multiple broadcast domains, each isolated at Layer 2.
Related concept
Read the scenario before looking for a memorised answer.
VPN
Why it's wrong here
VPNs provide encrypted tunnels over public networks, not broadcast domain segmentation.
NAT
Why it's wrong here
NAT translates IP addresses but does not segment broadcast domains.
Common exam traps
CompTIA often tests the misconception that subnetting alone can segment broadcast domains, but subnetting only divides IP address space; without VLANs, all devices on the same switch remain in one broadcast domain at Layer 2.
Detailed technical explanation
VLANs use 802.1Q trunking to tag Ethernet frames with a 12-bit VLAN ID (0–4095), allowing multiple VLANs to traverse a single switch trunk link. When a switch receives a broadcast frame on a VLAN, it forwards the frame only to ports that are members of that same VLAN, effectively isolating broadcast traffic. In real-world scenarios, VLANs are essential for separating guest Wi-Fi traffic from corporate data traffic on the same physical switch without adding routers or additional switches.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A help-desk technician troubleshoots why a newly connected PC cannot reach shared printers on the same floor. The cable is good, the switch port is active, but the PC is in VLAN 20 and the printers are in VLAN 10. The uplink trunk only allows VLAN 10. A trunk being up does not mean every VLAN crosses it.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Networking Concepts — study guide chapter
Learn the concepts, then practise the questions
Networking Concepts practice questions
Targeted practice on this topic area only
All N10-009 questions
520 questions across all exam domains
CompTIA Network+ N10-009 study guide
Full concept coverage aligned to exam objectives
N10-009 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise N10-009 questions linked to Networking Concepts.
Practise N10-009 questions linked to Network Implementation.
Practise N10-009 questions linked to Network Operations.
Practise N10-009 questions linked to Network Security.
Practise N10-009 questions linked to Network Troubleshooting.
Practise N10-009 questions linked to Network+ network fundamentals.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Networking Concepts — This question tests Networking Concepts — Read the scenario before looking for a memorised answer..
The correct answer is: VLANs — VLANs (Virtual Local Area Networks) allow a network engineer to logically segment a single physical LAN switch into multiple isolated broadcast domains without purchasing additional hardware. By assigning switch ports to different VLAN IDs, broadcast traffic is confined to ports within the same VLAN, effectively creating separate Layer 2 networks on the same switch infrastructure.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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 →
Keep practising
Last reviewed: Jun 30, 2026
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.