Multi-AZ three-tier web application on AWS with CloudFront CDN, WAF, and Application Load Balancer distributing traffic across EC2 and ECS compute in two availability zones. Application tier connects to RDS Primary/Standby, DynamoDB with cross-region replicas, and ElastiCache Redis for caching, all monitored by CloudWatch. This architecture demonstrates AWS best practices for fault tolerance, auto-scaling, and disaster recovery across isolated subnets and availability zones. Fork this diagram on Diagrams.so to customize instance types, add Auto Scaling Groups, or integrate additional AWS services like SNS or SQS. The design isolates public, application, and data subnets per AZ to enforce least-privilege network access and contain blast radius.