Multi-AZ FinTech architecture on AWS with three-tier isolation: DMZ presentation layer using ALB and t3.medium EC2 instances across AZ-1 and AZ-2, application layer with t3.large servers behind internal ALB on private subnets, and isolated data layer featuring RDS Aurora with read replicas and ElastiCache Redis for caching. AWS Shield Advanced, WAF, and Network Firewalls protect against DDoS and unauthorized access, while security groups enforce least-privilege rules between tiers. Route 53 provides DNS failover, CloudFront accelerates content delivery, and CloudWatch plus CloudTrail enable comprehensive monitoring and compliance auditing. Fork this diagram to customize instance types, subnet ranges, or add additional AWS services like Secrets Manager and KMS for encryption key management. This architecture demonstrates enterprise-grade availability and security patterns critical for regulated financial services workloads.