SAA-C03 Exam Dumps : AWS Certified Solutions Architect - Associate (SAA-C03)

Using an Application Load Balancer (ALB) allows for integration with AWS WAF to inspect all incoming traffic. Running the application on Amazon ECS provides a scalable and managed container orchestration service. Utilizing Amazon Aurora Serverless for the PostgreSQL database offers automatic scaling based on application demand, which is cost-effective for workloads with variable traffic patterns, such as higher traffic on weekdays and lower traffic on weekends.

The correct answer is A because the application is a global Voice over IP workload that needs low latency , high availability , and automated failover across AWS Regions . AWS Global Accelerator is specifically designed to improve the availability and performance of global applications by routing user traffic over the AWS global network to the optimal healthy endpoint. It uses static Anycast IP addresses , which means users connect through fixed IP addresses that do not depend on client-side DNS or IP address caching behavior.

This is especially valuable for latency-sensitive applications such as Voice over IP, where rapid routing decisions and fast failover are critical. Global Accelerator continuously monitors endpoint health and can automatically direct traffic to healthy endpoints in another AWS Region if a failure occurs. This supports the requirement for cross-Region failover with minimal disruption.

Option B is incorrect because Route 53 geolocation routing directs traffic based on user location, but DNS-based routing can be affected by client-side caching and does not provide the same performance acceleration or fast failover behavior as Global Accelerator. Option C is incorrect because Amazon CloudFront is primarily a content delivery network for HTTP and similar content distribution scenarios, not the preferred service for real-time Voice over IP traffic. Option D is incorrect because an Application Load Balancer does not by itself provide global routing or multi-Region failover.

AWS best practices for global, latency-sensitive applications recommend AWS Global Accelerator when the goal is to improve performance, use the AWS backbone network, and provide health-based failover without depending on DNS cache expiration. Therefore, AWS Global Accelerator with health checks is the best solution.

EC2 instances in private subnets cannot access the internet unless there is a NAT gateway or a NAT instance configured.

“To enable instances in a private subnet to connect to the internet or other AWS services, you can use a NAT gateway or NAT instance.”

— NAT Gateways – Amazon VPC

In this use case:

EC2 instances are in private subnets

They need to call external APIs (internet access)

The most operationally efficient and secure method is to place a NAT Gateway in a public subnet and update the route table for private subnets to route internet-bound traffic through it.

Incorrect Options:

A: Private subnets don’t support public IPs.

C: VPC peering doesn’t help reach the public internet.

D: Interface endpoints are for private connectivity to AWS services, not external APIs.