Which solution will meet these requirements with the LOWEST latency of reads and writes?
Implement Amazon DocumentDB (with MongoDB compatibility) in each of the six Regions.
Implement Amazon DynamoDB global tables in each of the six Regions.
Implement Amazon ElastiCache for Redis replication groups in each of the six Regions.
Implement Amazon Elasticsearch Service (Amazon ES) in each of the six Regions.
Explanations:
Amazon DocumentDB (with MongoDB compatibility) is primarily designed for document storage, not for low-latency, highly available distributed systems. It does not provide a native, multi-region replication feature with low latency like DynamoDB global tables.
Amazon DynamoDB global tables provide low-latency, multi-region replication. This solution ensures that the data is available in all six Regions with minimal delay for both reads and writes, making it ideal for the use case.
Amazon ElastiCache for Redis replication groups is designed for caching purposes, not for persistent data storage. While it can provide low-latency reads, it is not designed for multi-region, persistent data consistency and availability at scale.
Amazon Elasticsearch Service (Amazon ES) is optimized for search and analytics workloads, not for handling highly available, low-latency data writes and user consent storage. It is not suitable for storing user responses in a globally distributed, low-latency fashion.
My best guess is:
Implement Amazon DynamoDB global tables in each of the six Regions.