AWS 3-tier web application spanning two availability zones with WAF protection, Application Load Balancer, Auto Scaling EC2 instances, and RDS PostgreSQL primary-replica replication. Traffic flows from users through WAF and ALB to t3.medium EC2 instances in private subnets across AZ-1 and AZ-2, while application servers connect to both primary and read-replica RDS databases for write and read operations. This architecture demonstrates multi-AZ resilience, automatic scaling, and database high availability using managed AWS services within a VPC. Fork this diagram on Diagrams.so to customize instance types, subnet ranges, or add additional tiers like ElastiCache or CloudFront. The read replica enables read-heavy workloads to scale independently while maintaining synchronous replication from the primary database.