Business firewalls (e.g., Meraki, Fortinet, SonicWall, Palo Alto or similar), VPNs (IPsec, SSL VPN), and advanced networking concepts (e.g., VLANs, routing protocols like OSPF/BGP, Spanning Tree, QoS, network segmentation, SD-WAN). The Level III Technician will be responsible for advanced troubleshooting and resolving complex technical issues across network, server, and endpoint systems, managing IT infrastructure, and providing proactive system maintenance.