The answer is Virtual LAN (VLAN). A VLAN segments a single physical switch into multiple isolated broadcast domains at Layer 2, confining broadcast traffic to only those ports assigned to the same VLAN. This improves security by preventing devices in different VLANs from directly communicating without a router, and it reduces unnecessary traffic by limiting broadcast frames to their own logical segment. On the CompTIA Network+ N10-009 exam, this concept tests your understanding of how to achieve broadcast domain segmentation without adding extra hardware—a common trap is confusing VLANs with subnets (which operate at Layer 3) or assuming you need a separate physical switch for each domain. Remember the key distinction: VLANs create logical boundaries on the same switch, while subnets handle IP addressing. A helpful memory tip is “VLANs slice the switch, subnets slice the network.”
N10-009 Network Implementation Practice Question
This N10-009 practice question tests your understanding of network implementation. 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 needs to segment a single physical switch into multiple broadcast domains to improve security and reduce traffic. Which technology should be implemented?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Virtual LAN (VLAN)
A VLAN (Virtual LAN) segments a physical switch into multiple isolated broadcast domains at Layer 2. By assigning ports to different VLANs, broadcast traffic is confined to each VLAN, improving security and reducing unnecessary traffic. This directly meets the requirement without requiring additional hardware.
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.
✗
Spanning Tree Protocol (STP)
Why it's wrong here
STP prevents loops in redundant switch topologies, but does not segment broadcast domains.
✓
Virtual LAN (VLAN)
Why this is correct
VLANs create separate broadcast domains on a switch, meeting the requirement.
Related concept
Read the scenario before looking for a memorised answer.
✗
VLAN Trunking Protocol (VTP)
Why it's wrong here
VTP is used to manage VLAN configurations across switches, but it does not itself create broadcast domains.
✗
Access Control List (ACL)
Why it's wrong here
ACLs filter traffic based on rules, but they do not create separate broadcast domains.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CompTIA often tests the distinction between VLANs (which create broadcast domains) and VTP (which only propagates VLAN information), leading candidates to confuse configuration management with actual segmentation.
Detailed technical explanation
How to think about this question
VLANs work by tagging Ethernet frames with a 12-bit VLAN ID (802.1Q), allowing a single switch to maintain separate MAC address tables and spanning-tree instances per VLAN. In a real-world scenario, placing sensitive servers in VLAN 10 and guest users in VLAN 20 ensures that a broadcast storm in the guest network does not affect the servers, and inter-VLAN routing requires a Layer 3 device (router or Layer 3 switch).
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 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.
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 Implementation — This question tests Network Implementation — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Virtual LAN (VLAN) — A VLAN (Virtual LAN) segments a physical switch into multiple isolated broadcast domains at Layer 2. By assigning ports to different VLANs, broadcast traffic is confined to each VLAN, improving security and reducing unnecessary traffic. This directly meets the requirement without requiring additional hardware.
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.
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.