A Three-Tier Web Application Processes Orders from Customers

question 536

Multiple Choice

A three-tier web application processes orders from customers. The web tier consists of Amazon EC2 instances behind an Application Load Balancer, a middle tier of three EC2 instances decoupled from the web tier using Amazon SQS, and an Amazon DynamoDB backend. At peak times, customers who submit orders using the site have to wait much longer than normal to receive confirmations due to lengthy processing times. A solutions architect needs to reduce these processing times. Which action will be MOST effective in accomplishing this?

• A) Replace the SQS queue with Amazon Kinesis Data Firehose.
• B) Use Amazon ElastiCache for Redis in front of the DynamoDB backend tier.
• C) Add an Amazon CloudFront distribution to cache the responses for the web tier.
• D) Use Amazon EC2 Auto Scaling to scale out the middle tier instances based on the SQS queue depth.

---

Definitions:

Attachment

The enduring affectional tie that binds one person to another.

Ainsworth

Refers to Mary Ainsworth, a developmental psychologist known for her work on attachment theory, particularly the Strange Situation assessment.

Avoidant Attachment

A type of insecure attachment where individuals tend to keep distance from others and avoid emotional connection.

Ambiguous/resistant Attachment

A pattern of attachment characterized by anxiety and uncertainty in relationships, leading to clinginess and difficulty in trusting others.