Three-tier enterprise LAN architecture with DMZ, core switching, and VLAN segmentation across multiple floors. Traffic flows from Internet through a core router and firewall to a Layer 3 core switch, which distributes to separate distribution switches serving development, administration, and reception departments via dedicated VLANs. The DMZ hosts web and database servers on VLAN 10, while developer workstations (30x), admin stations (10x), and reception terminals (5x) connect through access switches on VLANs 20, 30, and 40 respectively. This hierarchical design isolates critical infrastructure, enables scalable departmental segmentation, and supports monitoring and WAF security controls at the core layer. Fork this diagram on Diagrams.so to customize IP ranges, add additional VLANs, or adapt the topology for your organization's floor plan and user count.