- A
Application Load Balancer (ALB) using HTTP/HTTPS listeners with host-based routing
Why wrong: ALB is a Layer 7 (application) load balancer designed for HTTP/HTTPS. It does not natively load balance arbitrary TCP protocols that do not use HTTP semantics.
- B
Network Load Balancer (NLB) using TCP listeners
NLB is a Layer 4 load balancer that supports TCP and UDP. When the traffic is routed to targets (for example, instance or IP targets), the backend connection maintains the original source IP/port at the networking layer, which supports IP-based auditing without requiring HTTP headers.
- C
Classic Load Balancer (CLB) configured for TCP health checks only
Why wrong: CLB is an older generation load balancer. For new designs needing high performance for TCP traffic and modern feature support, NLB is the recommended choice.
- D
API Gateway with a VPC Link to forward raw TCP traffic
Why wrong: API Gateway is designed for HTTP APIs (REST/HTTP/WebSocket). It does not provide Layer 4 raw TCP load balancing for arbitrary TCP application protocols.
SAA-C03 Design High-Performing Architectures Practice Question
This SAA-C03 practice question tests your understanding of design high-performing 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 team needs to distribute TCP traffic (not HTTP) across multiple services. The services must see the original client source IP for auditing. Which AWS load balancer 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 (NLB) using TCP listeners
A Network Load Balancer (NLB) is the best fit because it operates at Layer 4 (TCP/UDP) and preserves the original client source IP address by default, which is required for auditing. It can distribute raw TCP traffic across multiple services without inspecting application-layer headers, making it ideal for non-HTTP TCP workloads.
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 (ALB) using HTTP/HTTPS listeners with host-based routing
Why it's wrong here
ALB is a Layer 7 (application) load balancer designed for HTTP/HTTPS. It does not natively load balance arbitrary TCP protocols that do not use HTTP semantics.
When this WOULD be correct
When distributing HTTP/HTTPS traffic and needing advanced routing (e.g., host-based or path-based routing) with original client IP preserved via X-Forwarded-For headers.
- ✓
Network Load Balancer (NLB) using TCP listeners
Why this is correct
NLB is a Layer 4 load balancer that supports TCP and UDP. When the traffic is routed to targets (for example, instance or IP targets), the backend connection maintains the original source IP/port at the networking layer, which supports IP-based auditing without requiring HTTP headers.
Clue confirmation
The clue word "best" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Classic Load Balancer (CLB) configured for TCP health checks only
Why it's wrong here
CLB is an older generation load balancer. For new designs needing high performance for TCP traffic and modern feature support, NLB is the recommended choice.
When this WOULD be correct
A scenario where the requirement is to distribute TCP traffic across multiple EC2 instances using basic round-robin routing, and preserving the client IP is not needed. For example, a legacy application that only needs simple load balancing without advanced features like SNI or source IP preservation.
- ✗
API Gateway with a VPC Link to forward raw TCP traffic
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The SAA-C03 exam frequently reuses these exact scenarios with slightly different constraints.
✓Network Load Balancer (NLB) using TCP listenersCorrect answer▾
Why this is correct
NLB is a Layer 4 load balancer that supports TCP and UDP. When the traffic is routed to targets (for example, instance or IP targets), the backend connection maintains the original source IP/port at the networking layer, which supports IP-based auditing without requiring HTTP headers.
✗Application Load Balancer (ALB) using HTTP/HTTPS listeners with host-based routingWrong answer — click to see why▾
Why this is wrong here
ALB only supports HTTP/HTTPS listeners, not raw TCP traffic. It cannot distribute non-HTTP TCP traffic as required.
★ When this WOULD be the correct answer
When distributing HTTP/HTTPS traffic and needing advanced routing (e.g., host-based or path-based routing) with original client IP preserved via X-Forwarded-For headers.
Why candidates choose this
Candidates may assume ALB supports all TCP traffic because it is a common load balancer, or they overlook the requirement for non-HTTP TCP traffic.
✗Classic Load Balancer (CLB) configured for TCP health checks onlyWrong answer — click to see why▾
Why this is wrong here
Classic Load Balancer (CLB) does not preserve the original client source IP for TCP traffic; it uses its own IP as the source. The question requires preserving the client IP for auditing, which CLB cannot do.
★ When this WOULD be the correct answer
A scenario where the requirement is to distribute TCP traffic across multiple EC2 instances using basic round-robin routing, and preserving the client IP is not needed. For example, a legacy application that only needs simple load balancing without advanced features like SNI or source IP preservation.
Why candidates choose this
Candidates may think CLB is sufficient for TCP traffic because it supports TCP listeners and health checks, and they might overlook the specific requirement for preserving the original client source IP.
✗API Gateway with a VPC Link to forward raw TCP trafficWrong answer — click to see why▾
Why this is wrong here
API Gateway does not support raw TCP traffic; it is designed for HTTP/HTTPS and WebSocket APIs. It cannot forward arbitrary TCP streams to backend services.
★ When this WOULD be the correct answer
A team needs to expose RESTful or WebSocket APIs to external clients while keeping backend services in a private VPC. API Gateway with a VPC Link would securely forward HTTP/HTTPS requests to internal ALBs or NLBs.
Why candidates choose this
Candidates may think API Gateway can handle any protocol via VPC Link, but VPC Link only works with HTTP/HTTPS APIs, not raw TCP.
Analysis generated from the official SAA-C03blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often assume an Application Load Balancer can handle any TCP traffic because of its 'listener' terminology, but ALB strictly requires HTTP/HTTPS protocols and cannot forward raw TCP streams.
Detailed technical explanation
How to think about this question
NLBs preserve the client source IP by using the same IP address in the TCP handshake and forwarding packets at the flow level without modifying the IP header. This is achieved because the NLB does not terminate the TCP connection; it acts as a transparent proxy, passing the original source IP to the backend. In contrast, ALBs terminate the client connection and establish a new one to the target, which changes the source IP unless you rely on proxy protocol (NLB) or X-Forwarded-For (ALB).
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.
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 High-Performing Architectures — study guide chapter
Learn the concepts, then practise the questions
- →
Design High-Performing 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 High-Performing Architectures — This question tests Design High-Performing 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 (NLB) using TCP listeners — A Network Load Balancer (NLB) is the best fit because it operates at Layer 4 (TCP/UDP) and preserves the original client source IP address by default, which is required for auditing. It can distribute raw TCP traffic across multiple services without inspecting application-layer headers, making it ideal for non-HTTP TCP workloads.
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.