A blog site runs on EC2 instances in an Auto Scaling group behind an ALB and stores content on Amazon EFS. The site added video support and traffic increased tenfold, causing buffering and timeouts at peak times. Which is the most cost-effective and scalable deployment to resolve user performance issues?

Creating an Amazon CloudFront distribution with an S3 bucket origin for videos is the most cost-effective and scalable solution. CloudFront caches video content at edge locations globally, reducing latency and improving user experience by serving content closer to the user. S3 provides highly durable, scalable, and cost-effective storage for video files. This offloads traffic from the EC2 instances and EFS, addressing buffering and timeouts. Reconfiguring EFS to maximum I/O might improve performance but is more expensive and doesn't address global distribution or offload the EC2 instances effectively. Using instance store for content is not durable, as data is lost on instance termination, and copying to S3 at shutdown adds complexity and potential data loss. Creating a CloudFront distribution for all site content pointing to the ALB would cache static content but not dynamic content and would still direct all video requests to the ALB and EFS, which are the bottlenecks.