The answer is to update the route table for the private subnets to include a route to the S3 VPC Gateway Endpoint. This is correct because a VPC Gateway Endpoint for S3 enables private, cost-effective access to S3 without traversing the internet or requiring a NAT Gateway, using AWS’s internal network to route traffic directly through the endpoint and avoid data transfer costs. On the AWS Certified Advanced Networking Specialty ANS-C01 exam, this scenario tests your understanding of how Gateway Endpoints differ from Interface Endpoints—specifically that they use route table entries rather than ENIs, and that they are the most secure and cost-efficient choice for same-region S3 access. A common trap is selecting a NAT Gateway or Interface Endpoint, which incur additional costs and complexity. Memory tip: “Gateway for S3, Interface for everything else”—if the service is S3 or DynamoDB, think Gateway Endpoint and route table updates.
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.
A company has a VPC with public and private subnets. The public subnet has a NAT Gateway. The private subnet instances need to access an S3 bucket in the same region. Which THREE steps should the network engineer take to ensure the most cost-effective and secure access without traversing the internet?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Create a VPC Gateway Endpoint for S3.
Option A is correct because a VPC Gateway Endpoint for S3 provides private, cost-effective access to S3 without traversing the internet or requiring a NAT Gateway. It uses AWS's internal network and route table entries to direct S3 traffic through the endpoint, avoiding data transfer costs and improving security.
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.
✓
Create a VPC Gateway Endpoint for S3.
Why this is correct
Gateway Endpoints are free and provide private access to S3.
Related concept
Read the scenario before looking for a memorised answer.
✓
Attach an endpoint policy that allows access to the specific S3 bucket.
Why this is correct
The endpoint policy controls access to S3 via the endpoint.
Related concept
Read the scenario before looking for a memorised answer.
✗
Create a VPC Interface Endpoint for S3.
Why it's wrong here
Interface Endpoints for S3 are not supported in all regions and cost more.
✓
Update the route table for the private subnets to include a route to the S3 endpoint.
Why this is correct
Route tables must have a route to the endpoint prefix list.
Related concept
Read the scenario before looking for a memorised answer.
✗
Create a NAT Gateway in the public subnet.
Why it's wrong here
NATGateway is not cost-effective and would route traffic over the internet.
Common exam traps
Common exam trap: answer the scenario, not the keyword
AWS often tests the misconception that Interface Endpoints are required for all AWS services, but for S3 and DynamoDB, Gateway Endpoints are the correct, cost-effective choice, and candidates may incorrectly select Interface Endpoints due to familiarity with other services.
Detailed technical explanation
How to think about this question
VPC Gateway Endpoints use prefix lists and route table entries to route S3 traffic through AWS's private network, leveraging the S3 service's regional endpoint (e.g., s3.us-east-1.amazonaws.com). Unlike Interface Endpoints, Gateway Endpoints do not require Elastic Network Interfaces or incur hourly charges, making them ideal for high-volume S3 access. The endpoint policy can be scoped to specific buckets and actions, providing granular security without complex IAM roles.
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 startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
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 — 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: Create a VPC Gateway Endpoint for S3. — Option A is correct because a VPC Gateway Endpoint for S3 provides private, cost-effective access to S3 without traversing the internet or requiring a NAT Gateway. It uses AWS's internal network and route table entries to direct S3 traffic through the endpoint, avoiding data transfer costs and improving security.
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 →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A company has a VPC with public and private subnets. They have a web server in the public subnet that needs to make API calls to Amazon S3. The web server has a public IP. What is the MOST secure way to allow the web server to access S3 without traversing the internet?
medium
✓ A.Create a Gateway VPC Endpoint for S3 and add a route in the public subnet's route table to S3 via the endpoint
B.Place a forward proxy server in the public subnet and configure the web server to use it for S3
C.Create an Interface VPC Endpoint for S3 in the public subnet
D.Set up a NAT Gateway in the same subnet and route S3 traffic through it
Why A: Option C is correct because a Gateway VPC Endpoint for S3 allows private access to S3 without internet traffic, and it is free and highly available. Option A is wrong because a NAT Gateway is used for outbound internet access, but it still uses the internet. Option B is wrong because an Interface VPC Endpoint for S3 is also private but more expensive than Gateway Endpoint. Option D is wrong because a proxy server adds complexity and is not the most secure or simple solution.
Variation 2. A company has a VPC with multiple subnets. An EC2 instance in a private subnet needs to access an S3 bucket. Which AWS service should be used to allow this access without traversing the internet?
easy
A.Transit Gateway
B.NAT gateway
✓ C.VPC Gateway Endpoint for S3
D.Internet gateway
Why C: Option C is correct because a VPC Gateway Endpoint for S3 allows private access. Option A is incorrect because a NAT gateway is for internet access. Option B is incorrect because an Internet Gateway is for internet access. Option D is incorrect because a Transit Gateway is for connecting networks.
Variation 3. A company has a VPC with multiple subnets. An EC2 instance in a private subnet needs to access an S3 bucket to download files. The company wants to avoid using a NAT gateway and minimize latency. Which solution should be used?
hard
✓ A.Create a VPC endpoint for S3 and attach it to the private subnet's route table.
B.Place the instance in a public subnet and use a NAT gateway.
C.Use a VPC endpoint for EC2.
D.Use an internet gateway and a route to 0.0.0.0/0.
Why A: Option C is correct because a VPC endpoint for S3 allows private access without NAT or IGW. A is not for S3. B adds latency. D is not for S3.
Last reviewed: Jun 30, 2026
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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.
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