FurLink's three-tier network architecture separates public-facing web services from protected backend databases using DMZ and internal firewall segmentation across VLAN 10, VLAN 20, and VLAN 99. Public users connect via HTTPS through a perimeter firewall to a load balancer distributing traffic across four PHP application servers, which route database queries through an internal firewall to primary and replica MySQL servers. The design implements defense-in-depth with dual firewalls, VPN-gated management access, and clear network boundaries that enforce least-privilege communication between tiers. Fork this diagram on Diagrams.so to customize IP ranges, add additional VLANs, or adapt the topology for your organization's security and availability requirements. This architecture exemplifies the three-tier DMZ pattern commonly used in regulated environments requiring strict network segmentation and audit trails.