- A
Attach a NAT gateway to the VPC and add a route for ::/0 to the NAT gateway in the public subnet route table.
Why wrong: NAT gateways support IPv4 only.
- B
Attach an internet gateway to the VPC and add a route for 0.0.0.0/0 to the internet gateway in the public subnet route table.
Why wrong: That is for IPv4, not IPv6.
- C
Set up a NAT64 translation service to convert IPv6 requests to IPv4.
Why wrong: Unnecessary for simple outbound-only IPv6 access.
- D
Attach an egress-only internet gateway to the VPC and add a route for ::/0 to the egress-only internet gateway in the public subnet route table.
Provides outbound-only IPv6 internet access.
Question 796 of 1,705
ANS-C01 Network Implementation Practice Question
This ANS-C01 practice question tests your understanding of network implementation. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 company is deploying a VPC with IPv6 support. The VPC has a CIDR block of 10.0.0.0/16 and an assigned IPv6 CIDR block of 2600:1f16:xxxx:xxxx::/56. The company wants EC2 instances in a public subnet to be able to communicate with the internet using IPv6. Which configuration is necessary?
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
✓
Attach an egress-only internet gateway to the VPC and add a route for ::/0 to the egress-only internet gateway in the public subnet route table.
Option D is correct because an egress-only internet gateway (EIGW) is the AWS-managed service designed to enable outbound-only IPv6 communication from a VPC to the internet. Since IPv6 addresses are globally unique and publicly routable, a NAT gateway (used for IPv4) is not needed; instead, the EIGW allows instances to initiate outbound traffic while preventing any unsolicited inbound connections. Adding a route for ::/0 to the EIGW in the public subnet route table directs all outbound IPv6 traffic through it.
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.
- ✗
Attach a NAT gateway to the VPC and add a route for ::/0 to the NAT gateway in the public subnet route table.
Why it's wrong here
NAT gateways support IPv4 only.
- ✗
Attach an internet gateway to the VPC and add a route for 0.0.0.0/0 to the internet gateway in the public subnet route table.
Why it's wrong here
That is for IPv4, not IPv6.
- ✗
Set up a NAT64 translation service to convert IPv6 requests to IPv4.
Why it's wrong here
Unnecessary for simple outbound-only IPv6 access.
- ✓
Attach an egress-only internet gateway to the VPC and add a route for ::/0 to the egress-only internet gateway in the public subnet route table.
Why this is correct
Provides outbound-only IPv6 internet access.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the egress-only internet gateway with a NAT gateway or assume that an internet gateway alone suffices for IPv6, forgetting that the internet gateway supports both inbound and outbound traffic, whereas the EIGW is specifically required for outbound-only IPv6 communication to prevent inbound connections.
Detailed technical explanation
How to think about this question
An egress-only internet gateway operates at layer 3 and uses an asymmetric routing model: it forwards outbound IPv6 packets from the VPC to the internet but drops any inbound traffic that was not initiated from within the VPC. This is achieved by the EIGW being stateful only for outbound flows, unlike a standard internet gateway which allows bidirectional traffic. In real-world scenarios, this is critical for workloads that must maintain public IPv6 reachability for outbound connections (e.g., software updates, API calls) while avoiding exposure to unsolicited inbound attacks.
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 healthcare organisation deploys an application with a public-facing web tier and a private database tier. The database subnet has no public IP and only accepts connections from the web tier's security group. Questions like this test whether you can design cloud network isolation using VNets/VPCs, subnets, and security group rules.
Visual reference
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Network Implementation — study guide chapter
Learn the concepts, then practise the questions
- →
Network Implementation practice questions
Targeted practice on this topic area only
- →
All ANS-C01 questions
1,705 questions across all exam domains
- →
AWS Certified Advanced Networking Specialty ANS-C01 study guide
Full concept coverage aligned to exam objectives
- →
ANS-C01 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related ANS-C01 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Network Management and Operations practice questions
Practise ANS-C01 questions linked to Network Management and Operations.
Network Security, Compliance and Governance practice questions
Practise ANS-C01 questions linked to Network Security, Compliance and Governance.
Network Design practice questions
Practise ANS-C01 questions linked to Network Design.
Network Implementation practice questions
Practise ANS-C01 questions linked to Network Implementation.
ANS-C01 fundamentals practice questions
Practise ANS-C01 questions linked to ANS-C01 fundamentals.
ANS-C01 scenario practice questions
Practise ANS-C01 questions linked to ANS-C01 scenario.
ANS-C01 troubleshooting practice questions
Practise ANS-C01 questions linked to ANS-C01 troubleshooting.
Practice this exam
Start a free ANS-C01 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this ANS-C01 question test?
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: Attach an egress-only internet gateway to the VPC and add a route for ::/0 to the egress-only internet gateway in the public subnet route table. — Option D is correct because an egress-only internet gateway (EIGW) is the AWS-managed service designed to enable outbound-only IPv6 communication from a VPC to the internet. Since IPv6 addresses are globally unique and publicly routable, a NAT gateway (used for IPv4) is not needed; instead, the EIGW allows instances to initiate outbound traffic while preventing any unsolicited inbound connections. Adding a route for ::/0 to the EIGW in the public subnet route table directs all outbound IPv6 traffic through it.
What should I do if I get this ANS-C01 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 →
Keep practising
More ANS-C01 practice questions
- A financial services company has a VPC with a public subnet and a private subnet. EC2 instances in the private subnet ne…
- A company is designing a network security architecture for a multi-account environment using AWS Transit Gateway. The se…
- A company is using AWS Direct Connect to connect its on-premises network to AWS. The company wants to encrypt all traffi…
- A company uses AWS Transit Gateway to connect multiple VPCs and on-premises networks via AWS Site-to-Site VPN. The secur…
- A company runs a web application on EC2 instances behind an Application Load Balancer (ALB). The application must be acc…
- A global e-commerce company uses a hub-and-spoke network topology with a transit VPC in us-east-1. Each spoke VPC has an…
Last reviewed: Jul 4, 2026
This ANS-C01 practice question is part of Courseiva's free Amazon Web Services 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 ANS-C01 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.