AWS Certified Solutions Architect – Associate (SAA-C03) — Question 296

A company is hosting a three-tier ecommerce application in the AWS Cloud. The company hosts the website on Amazon S3 and integrates the website with an API that handles sales requests. The company hosts the API on three Amazon EC2 instances behind an Application Load Balancer (ALB). The API consists of static and dynamic front-end content along with backend workers that process sales requests asynchronously.

The company is expecting a significant and sudden increase in the number of sales requests during events for the launch of new products.

What should a solutions architect recommend to ensure that all the requests are processed successfully?

Answer options

• A. Add an Amazon CloudFront distribution for the dynamic content. Increase the number of EC2 instances to handle the increase in traffic.
• B. Add an Amazon CloudFront distribution for the static content. Place the EC2 instances in an Auto Scaling group to launch new instances based on network traffic.
• C. Add an Amazon CloudFront distribution for the dynamic content. Add an Amazon ElastiCache instance in front of the ALB to reduce traffic for the API to handle.
• D. Add an Amazon CloudFront distribution for the static content. Add an Amazon Simple Queue Service (Amazon SQS) queue to receive requests from the website for later processing by the EC2 instances.

Correct answer: D

Explanation

Because the backend processes sales requests asynchronously, implementing an Amazon SQS queue is the best way to decouple the architecture and buffer sudden spikes in traffic without losing requests. Using Amazon CloudFront for static content offloads traffic from the origin, improving overall application performance. Other options do not address the asynchronous processing requirement or fail to prevent potential data loss during sudden traffic spikes before EC2 instances can scale out.