The optimal solution must address two key aspects: data locality and traffic routing. Given that over 90% of the database traffic is read-only, creating a cross-Region read replica for the Amazon RDS database is the most efficient and native AWS solution. This places a readable copy of the data in the new Europe Region, significantly reducing data access latency for European users. To complement this, Amazon Route 53 latency-based routing should be used. This policy directs users to the AWS Region that provides the lowest network latency for them, ensuring that both US and European users are automatically routed to their nearest and fastest application endpoint (API Gateway), thereby minimizing report download times.

A. An AWS DMS full load task is a one-time data migration. It does not provide continuous replication, so the database in the new Region would quickly become outdated.

B. While AWS DMS with Change Data Capture (CDC) provides replication, a native RDS cross-Region read replica is a simpler, more managed, and purpose-built solution for this use case.

D. Geolocation routing directs users based on their geographic origin, which is a reasonable proxy for latency. However, latency-based routing is more precise as it routes based on actual measured network performance to the AWS Regions.

1. Amazon RDS User Guide: "A cross-Region read replica is used to reduce latency for read queries. If you have a read-heavy workload and your users are globally distributed

you can create one or more read replicas in various AWS Regions to serve read traffic closer to your users."

Source: AWS Documentation

Amazon RDS User Guide

"Working with Amazon RDS read replicas

" Section: "Cross-Region read replicas."

2. Amazon Route 53 Developer Guide: "Latency-based routing lets you route your traffic to the AWS Region that provides the best latency (lowest network latency) and the best experience for your users. When Route 53 receives a query for your domain or subdomain

it determines which AWS Regions you've created latency records for

determines which region gives the user the lowest latency

and then selects a latency record for that region."

Source: AWS Documentation

Amazon Route 53 Developer Guide

"Choosing a routing policy

" Section: "Latency-based routing."

3. AWS Well-Architected Framework - Performance Efficiency Pillar: "To reduce latency

you can locate your resources closer to your users. You can do this by selecting the AWS Regions and edge locations that are closest to your users." This principle supports the use of both cross-Region resources (like the read replica) and latency-aware routing.

Source: AWS Well-Architected Framework

Performance Efficiency Pillar (aws-well-architected-framework.pdf)

Page 29

"Select the best performing architecture."