The correct answer is to deploy Network Firewall endpoints in multiple Availability Zones for high availability and to configure stateful rule groups to inspect traffic at the application layer. Deploying across multiple AZs ensures that firewall inspection remains resilient against an AZ failure, which is a fundamental high-availability best practice for any critical network component. Stateful rule groups, unlike stateless rules, can track connection state and perform deep packet inspection up to layer 7, allowing you to block threats like SQL injection or malware based on application data. On the AWS Certified Advanced Networking Specialty ANS-C01 exam, this question tests your understanding of how Network Firewall integrates with VPC routing and subnet design; a common trap is assuming stateless rules are the primary inspection method, but the exam emphasizes stateful inspection for advanced security. Remember the mnemonic "HA and Stateful" — high availability across zones plus stateful application-layer inspection are the two pillars of a secure VPC firewall deployment.
ANS-C01 Network Implementation Practice Question
This ANS-C01 practice question tests your understanding of network implementation. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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.
Which TWO of the following are best practices for securing a VPC with AWS Network Firewall? (Choose two.)
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "best"
Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Deploy firewall endpoints in at least two Availability Zones for high availability.
Correct: B (deploy in multiple AZs for HA) and D (use stateful rules for traffic inspection). A is wrong because it should be in a dedicated subnet. C is wrong because stateless rules are not the primary use case. E is wrong because Network Firewall supports both stateful and stateless.
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.
✓
Deploy firewall endpoints in at least two Availability Zones for high availability.
Why this is correct
Ensures resilience.
Clue confirmation
The clue word "best" in the question point toward this answer.
Use Network Firewall only for outbound traffic filtering.
Why it's wrong here
It can filter both inbound and outbound.
✗
Deploy the firewall in the same subnet as the workload for low latency.
Why it's wrong here
Dedicated subnet is recommended.
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
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
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 Implementation — This question tests Network Implementation — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Deploy firewall endpoints in at least two Availability Zones for high availability. — Correct: B (deploy in multiple AZs for HA) and D (use stateful rules for traffic inspection). A is wrong because it should be in a dedicated subnet. C is wrong because stateless rules are not the primary use case. E is wrong because Network Firewall supports both stateful and stateless.
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.
Are there clue words in this question I should notice?
Yes — watch for: "best". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.
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 →
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 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.