Quick Answer
The correct choice is 2001:db8:1::1 because IPv6 prefix matching with a /32 prefix requires that the first 32 bits of the address exactly match the prefix. The prefix 2001:db8::/32 expands to 2001:0db8 in hexadecimal, meaning any address starting with those 32 bits belongs to the same network. On the CompTIA Network+ N10-009 exam, this concept tests your ability to recognize that IPv6 addresses are matched by their fixed-length prefix, not by the full address length. A common trap is assuming that the prefix ends at a colon or that the double colon implies a shorter match, but the /32 always locks the first four hextets. To remember, think of the /32 as a “four-hex block” rule: the first four groups of four hex digits must stay the same, while everything after can vary.
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.
An IPv6 address has the prefix 2001:db8::/32. Which of the following IP addresses belongs to the same prefix?
2001:db8:1::1
The first 32 bits are 2001:0db8, which matches the prefix 2001:db8::/32.
2001:db9::1
Why wrong: The first 32 bits are 2001:0db9, which differs from 2001:0db8, so it is not in the same /32 prefix.
2001:db7::1
Why wrong: The first 32 bits are 2001:0db7, which differs from 2001:0db8.
fe80::1
Why wrong: fe80::1 is a link-local address and belongs to the fe80::/10 prefix, not 2001:db8::/32.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
2001:db8:1::1
The prefix 2001:db8::/32 means the first 32 bits of the address must be 2001:0db8. Option A (2001:db8:1::1) expands to 2001:0db8:0001:0000:0000:0000:0000:0001, which matches the first 32 bits exactly, so it belongs to the same /32 prefix.
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.
2001:db8:1::1
Why this is correct
The first 32 bits are 2001:0db8, which matches the prefix 2001:db8::/32.
Related concept
Read the scenario before looking for a memorised answer.
2001:db9::1
Why it's wrong here
The first 32 bits are 2001:0db9, which differs from 2001:0db8, so it is not in the same /32 prefix.
2001:db7::1
Why it's wrong here
The first 32 bits are 2001:0db7, which differs from 2001:0db8.
fe80::1
Why it's wrong here
fe80::1 is a link-local address and belongs to the fe80::/10 prefix, not 2001:db8::/32.
Common exam traps
Cisco often tests the misconception that the double-colon (::) compresses the prefix itself, leading candidates to incorrectly assume that 2001:db8::/32 matches any address starting with 2001:db8, even if the second hextet is altered (e.g., 2001:db9 or 2001:db7).
Detailed technical explanation
IPv6 prefixes are expressed in CIDR notation (e.g., /32), where the prefix length indicates the number of fixed bits from the left. The 2001:db8::/32 prefix is reserved for documentation (RFC 3849) and is commonly used in examples and exams. When comparing addresses to a prefix, you must expand any double-colon (::) and compare the first 32 bits (four hextets: 2001:0db8) without modification.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the N10-009 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
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: 2001:db8:1::1 — The prefix 2001:db8::/32 means the first 32 bits of the address must be 2001:0db8. Option A (2001:db8:1::1) expands to 2001:0db8:0001:0000:0000:0000:0000:0001, which matches the first 32 bits exactly, so it belongs to the same /32 prefix.
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 →
Last reviewed: Jun 11, 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.