Multi-AZ layered architecture for an AWS travel portal spanning four user personas—employees, admins, IT support, and suppliers—across Frankfurt region with Route 53 DNS, CloudFront CDN, WAF v2, and ALB routing to Lambda-based application, business, integration, and data layers. Traffic flows from external users through the public internet to CloudFront and WAF v2, then to an Application Load Balancer in the DMZ, which routes requests to authentication and portal Lambdas in public subnets across AZ-1 and AZ-2. Business logic Lambdas in private subnets handle authorization, booking rules, reporting, and notifications; integration Lambdas connect to external systems (CTC, UPSA, hotel booking, Uber) via SQS queues; and a data layer provides RDS primary/read replicas, ElastiCache Redis, EFS, and S3 with multi-AZ redundancy. This architecture demonstrates enterprise-grade availability, security segmentation, and scalability for complex travel workflows. Fork and customize this diagram on Diagrams.so to adapt subnets, Lambda concurrency, or add additional integrations. Consider adding VPC Flow Logs and GuardDuty for enhanced threat detection in production deployments.