- A
Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0
Why wrong: While possible, the security group already provides this; NACL is optional.
- B
Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0 and outbound ephemeral ports
NACL on public subnet provides stateless filtering for inbound HTTPS and outbound responses.
- C
Network ACL on the private subnet allowing inbound 3306 from the public subnet CIDR
Why wrong: NACL is stateless and can be used, but the security group is the recommended control.
- D
Security group for application servers allowing inbound 3306 from the web server security group
This ensures only web servers can access the application servers on the database port.
- E
Security group for web servers allowing inbound 443 from 0.0.0.0/0
This allows HTTPS traffic from the internet to the web servers.
ANS-C01 Network Security, Compliance and Governance Practice Question
This ANS-C01 practice question tests your understanding of network security, compliance and governance. 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 designing a network security solution for a VPC that hosts a multi-tier web application. The web servers are in a public subnet, and the application servers are in a private subnet. The company wants to ensure that the web servers can only be accessed on port 443 from the internet, and the application servers can only be accessed from the web servers on port 3306. Which THREE components should be configured?
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
Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0 and outbound ephemeral ports
The correct components are: a security group for web servers allowing inbound 443 from 0.0.0.0/0 (E), a security group for application servers allowing inbound 3306 from the web server security group (D), and a network ACL on the public subnet allowing inbound 443 and outbound ephemeral ports (B) to add a stateless filtering layer. Option A is incorrect because the NACL rule lacks an outbound rule for return traffic, making it incomplete. Option C is unnecessary because the access control for the private subnet is best achieved with security groups, and a NACL is not required for this purpose.
Key principle: Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0
Why it's wrong here
While possible, the security group already provides this; NACL is optional.
- ✓
Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0 and outbound ephemeral ports
- ✗
Network ACL on the private subnet allowing inbound 3306 from the public subnet CIDR
Why it's wrong here
NACL is stateless and can be used, but the security group is the recommended control.
- ✓
Security group for application servers allowing inbound 3306 from the web server security group
Why this is correct
This ensures only web servers can access the application servers on the database port.
Related concept
CIDR notation defines the prefix length.
- ✓
Security group for web servers allowing inbound 443 from 0.0.0.0/0
Common exam traps
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Detailed technical explanation
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
Key takeaway
Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
Visual reference
What to study next
Got this wrong? Here's your next step.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related ANS-C01 subnetting questions on CIDR, address ranges, and subnet selection.
- →
Network Security, Compliance and Governance — study guide chapter
Learn the concepts, then practise the questions
- →
Network Security, Compliance and Governance 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 Security, Compliance and Governance — This question tests Network Security, Compliance and Governance — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Network ACL on the public subnet allowing inbound 443 from 0.0.0.0/0 and outbound ephemeral ports — The correct components are: a security group for web servers allowing inbound 443 from 0.0.0.0/0 (E), a security group for application servers allowing inbound 3306 from the web server security group (D), and a network ACL on the public subnet allowing inbound 443 and outbound ephemeral ports (B) to add a stateless filtering layer. Option A is incorrect because the NACL rule lacks an outbound rule for return traffic, making it incomplete. Option C is unnecessary because the access control for the private subnet is best achieved with security groups, and a NACL is not required for this purpose.
What should I do if I get this ANS-C01 question wrong?
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related ANS-C01 subnetting questions on CIDR, address ranges, and subnet selection.
What is the key concept behind this question?
CIDR notation defines the prefix length.
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: Jun 20, 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.