How can session data be externalized, keeping latency at the LOWEST possible value?
Create an Amazon RDS instance, then implement session handling at the application level to leverage a database inside the RDS database instance for session data storage.
Implement a shared file system solution across the underlying Amazon EC2 instances, then implement session handling at the application level to leverage the shared file system for session data storage.
Create an Amazon ElastiCache Memcached cluster, then implement session handling at the application level to leverage the cluster for session data storage.
Create an Amazon DynamoDB table, then implement session handling at the application level to leverage the table for session data storage.
Explanations:
Amazon RDS is not designed for low-latency access to session data, as relational databases have higher latency compared to caching solutions.
Shared file systems can introduce higher latency and are not optimized for fast, scalable session data storage. It also complicates fault tolerance.
Amazon ElastiCache Memcached is an in-memory caching solution, providing low-latency, high-performance access to session data. It is ideal for externalizing session state.
Amazon DynamoDB is a NoSQL database designed for high scalability, but it has higher latency compared to in-memory solutions like ElastiCache, making it suboptimal for session storage.
I systematize that the answer is:
Create an Amazon ElastiCache Memcached cluster, then implement session handling at the application level to leverage the cluster for session data storage.