Cisco 3-tier network architecture, data center, modern infrastructure, multiple switches, routers, servers, firewall, VPN, WAN, LAN, Wi-Fi, high-performance cables, sleek metal racks, blinking LED lights, futuristic ambiance, complex wiring, air conditioning units, ventilation system, raised floor, server rooms, data storage, cloud computing, virtualization, scalability, reliability, security, 3D isometric view, detailed textures, metallic reflections, soft ambient lighting.