A new application runs on Amazon EC2 On-Demand Instances that scale frequently across multiple Availability Zones behind an Application Load Balancer (ALB). The architecture must support distributed session data management and the company is willing to modify application code if needed. What should the solutions architect do to provide distributed session data management?

Amazon ElastiCache (for Redis or Memcached) is an in-memory data store ideal for managing distributed session data. Its high performance and low latency ensure quick access to session information, which is crucial for applications scaling across multiple Availability Zones. Since the company is willing to modify application code, integrating ElastiCache is a viable and robust solution. Session affinity (sticky sessions) on the ALB forces a user's requests to be routed to the same EC2 instance. While it can maintain session data on the instance, it hinders application scalability and resilience, as instance failures would lead to session loss and uneven load distribution. AWS Systems Manager Session Manager is for managing EC2 instances, not for application session data. The GetSessionToken API is used for generating temporary security credentials, not for managing application session data.