Multi-tier hotel management system with DMZ perimeter security, WAF, CDN, and load balancing protecting guest-facing and staff interfaces. Traffic flows through Nginx reverse proxy into five internal VLANs: presentation (HTML/CSS/JS, Django templates, guest/staff UIs), application (Django views, REST APIs, auth), business logic (booking, payments, messaging, refunds), data (PostgreSQL primary/replica, Redis cache, object/file storage), and integration (notification service, monitoring, payment gateways). PostgreSQL primary replicates to read replica; integration gateway bridges PayMongo, GCash, Maya, and Stripe APIs; notification service handles email delivery. This architecture demonstrates defense-in-depth with network segmentation, database redundancy, and centralized payment processing for secure, scalable hotel operations. Fork and customize this diagram on Diagrams.so to adapt VLANs, add monitoring dashboards, or swap payment providers. Consider adding DDoS protection and SSL/TLS termination details for production deployments.