PC to switch connectivity: cabling, signaling, ports, link lights.
Switching, VLANs, and Spanning Tree Protocol.
IP addressing, routing, and subnetting.
TCP, UDP, ports, and the handshake/teardown flow.
Sessions and dialog control between hosts.
Data representation, encoding, and TLS.
HTTP, DNS, and application-layer protocols.
Cisco IOS-XE & Arista EOS BGP config and troubleshooting.
Why they'll ask, likely questions & scenarios for the branch network, firewall estate, and DR programme you'd inherit.
SOC/EDR triage, vulnerability & patch management, wireless estate, and vendor governance interview prep.
What really happens, step by step, from cable-in to a page loading — link, DHCP, ARP, routing, NAT, firewall, and back.
DNS, TCP handshake, TLS handshake, HTTP request/response, and browser render — in the order they actually happen.