- A
Application Load Balancer, because it provides advanced routing for all protocols.
Why wrong: An Application Load Balancer is designed for HTTP and HTTPS traffic, not arbitrary TCP protocols. It can do content-based routing for web workloads, but it does not meet the requirement for a custom TCP service with static IPs and minimal latency. Using ALB would mismatch the protocol and the performance profile of the application.
- B
Network Load Balancer, because it supports TCP, static IPs, and very low latency.
A Network Load Balancer is the best fit for a custom TCP service that needs extremely low latency and static IP addresses. NLB operates at Layer 4, preserves high throughput, and is commonly used when protocol simplicity and performance matter more than application-layer routing features. It matches the workload's network requirements without adding unnecessary HTTP-specific behavior.
- C
Amazon API Gateway, because it can front any network protocol with throttling.
Why wrong: API Gateway is focused on API management for HTTP-based request/response patterns, not arbitrary TCP protocols. It provides useful controls such as throttling and authorization, but it is not a drop-in solution for a low-latency custom TCP service. The protocol mismatch makes it the wrong tool for this use case.
- D
Amazon CloudFront, because it can route traffic to EC2 instances at the edge.
Why wrong: CloudFront is an edge content delivery network optimized for caching and accelerating HTTP and HTTPS content. It is not a general TCP load balancer and cannot directly satisfy a custom TCP protocol requirement. While it can improve web delivery, it does not provide the static IP and Layer 4 behavior this service needs.
Quick Answer
The answer is the Network Load Balancer (NLB). This is the correct choice because the NLB operates at Layer 4, handling TCP traffic natively without inspecting application-layer headers, which delivers the very low latency required by a legacy market-data service. It also provides static IP addresses per Availability Zone, meeting the need for a fixed IP at the load-balancing layer for a custom TCP protocol. On the SAA-C03 exam, this scenario tests your ability to distinguish between load balancer types: the Application Load Balancer (ALB) is Layer 7 and cannot handle raw TCP or static IPs, while the NLB is the only one that supports both. A common trap is assuming any load balancer can assign static IPs, but only the NLB offers this. Memory tip: think "N for Network, N for Native TCP, N for No latency overhead."
SAA-C03 Design Secure Architectures Practice Question
This SAA-C03 practice question tests your understanding of design secure architectures. 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 legacy market-data service runs on EC2 and exposes a custom TCP protocol. Clients must connect over TCP with very low latency, and the team wants static IP addresses at the load-balancing layer. Which AWS service is the best fit?
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 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 Load Balancer, because it supports TCP, static IPs, and very low latency.
The Network Load Balancer (NLB) operates at Layer 4, supports TCP traffic natively, provides static IP addresses per Availability Zone, and delivers very low latency by processing packets without inspecting application-layer headers. This makes it the ideal choice for a legacy market-data service that requires a custom TCP protocol and fixed IPs at the load-balancing layer.
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.
- ✗
Application Load Balancer, because it provides advanced routing for all protocols.
Why it's wrong here
An Application Load Balancer is designed for HTTP and HTTPS traffic, not arbitrary TCP protocols. It can do content-based routing for web workloads, but it does not meet the requirement for a custom TCP service with static IPs and minimal latency. Using ALB would mismatch the protocol and the performance profile of the application.
- ✓
Network Load Balancer, because it supports TCP, static IPs, and very low latency.
Why this is correct
A Network Load Balancer is the best fit for a custom TCP service that needs extremely low latency and static IP addresses. NLB operates at Layer 4, preserves high throughput, and is commonly used when protocol simplicity and performance matter more than application-layer routing features. It matches the workload's network requirements without adding unnecessary HTTP-specific behavior.
Clue confirmation
The clue word "best" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Amazon API Gateway, because it can front any network protocol with throttling.
Why it's wrong here
API Gateway is focused on API management for HTTP-based request/response patterns, not arbitrary TCP protocols. It provides useful controls such as throttling and authorization, but it is not a drop-in solution for a low-latency custom TCP service. The protocol mismatch makes it the wrong tool for this use case.
- ✗
Amazon CloudFront, because it can route traffic to EC2 instances at the edge.
Why it's wrong here
CloudFront is an edge content delivery network optimized for caching and accelerating HTTP and HTTPS content. It is not a general TCP load balancer and cannot directly satisfy a custom TCP protocol requirement. While it can improve web delivery, it does not provide the static IP and Layer 4 behavior this service needs.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the ALB's 'advanced routing' capabilities with support for all protocols, but ALB is strictly Layer 7 and cannot handle raw TCP or custom protocols, making NLB the only correct choice for TCP with static IPs and low latency.
Detailed technical explanation
How to think about this question
Under the hood, an NLB uses a flow-hash algorithm (based on source IP, source port, destination IP, destination port, and protocol) to route packets to a target, preserving the original client IP address by default. For ultra-low-latency workloads like market-data feeds, the NLB can be configured with a UDP listener alongside TCP, and it supports enabling client IP preservation and proxy protocol v2 for logging. A real-world scenario is a financial trading platform where each NLB node gets a static Elastic IP per AZ, allowing firewall rules to whitelist only those IPs while maintaining sub-millisecond latency.
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
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.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Design Secure Architectures — study guide chapter
Learn the concepts, then practise the questions
- →
Design Secure Architectures practice questions
Targeted practice on this topic area only
- →
All SAA-C03 questions
1,040 questions across all exam domains
- →
SAA-C03 study guide
Full concept coverage aligned to exam objectives
- →
SAA-C03 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related SAA-C03 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Design Secure Architectures practice questions
Practise SAA-C03 questions linked to Design Secure Architectures.
Design Resilient Architectures practice questions
Practise SAA-C03 questions linked to Design Resilient Architectures.
Design High-Performing Architectures practice questions
Practise SAA-C03 questions linked to Design High-Performing Architectures.
Design Cost-Optimized Architectures practice questions
Practise SAA-C03 questions linked to Design Cost-Optimized Architectures.
SAA-C03 VPC practice questions
Practise SAA-C03 questions linked to SAA-C03 VPC.
SAA-C03 S3 lifecycle policy questions
Practise SAA-C03 questions linked to SAA-C03 S3 lifecycle policy questions.
SAA-C03 RDS Multi-AZ questions
Practise SAA-C03 questions linked to SAA-C03 RDS Multi-AZ questions.
SAA-C03 IAM policy practice questions
Practise SAA-C03 questions linked to SAA-C03 IAM policy.
SAA-C03 Route 53 failover questions
Practise SAA-C03 questions linked to SAA-C03 Route 53 failover questions.
SAA-C03 CloudFront practice questions
Practise SAA-C03 questions linked to SAA-C03 CloudFront.
SAA-C03 NAT gateway questions
Practise SAA-C03 questions linked to SAA-C03 NAT gateway questions.
SAA-C03 VPC endpoint questions
Practise SAA-C03 questions linked to SAA-C03 VPC endpoint questions.
Practice this exam
Start a free SAA-C03 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 SAA-C03 question test?
Design Secure Architectures — This question tests Design Secure Architectures — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Network Load Balancer, because it supports TCP, static IPs, and very low latency. — The Network Load Balancer (NLB) operates at Layer 4, supports TCP traffic natively, provides static IP addresses per Availability Zone, and delivers very low latency by processing packets without inspecting application-layer headers. This makes it the ideal choice for a legacy market-data service that requires a custom TCP protocol and fixed IPs at the load-balancing layer.
What should I do if I get this SAA-C03 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
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?
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 SAA-C03 practice questions
- A content publishing system uses Lambda functions that call an unreliable third-party API. Failed events must be retaine…
- A startup runs two EC2-based workloads in the same AWS Region. Its customer-facing API is always on, and its nightly vid…
- A warehouse integration service must use shared file storage across Linux EC2 instances in multiple Availability Zones.…
- A team runs a stateless web app on Amazon EC2 behind an Application Load Balancer. During traffic spikes, new EC2 instan…
- A service in private subnets downloads product images from Amazon S3 and stores job state in DynamoDB. A NAT Gateway is…
- A static site is hosted in Amazon S3 and delivered by CloudFront. After a frontend release, the same JavaScript bundles…
Last reviewed: Jun 11, 2026
This SAA-C03 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 SAA-C03 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.