How Ping works, Trace route works, NAT, Active and Passive FTP, If a packet fails what are the debugging steps you do starting from your device to the destination host, Packet forwarding, IPV4 and IPV6, Flow control and congestion Control, DHCP Full process, Radius Full process with AAA ports, OSPF, Deep Packet Inspection, they looks whether we have for deep understanding of our product and how its deployed in real time environment. I worked for similar product so they asked to give a repro for there customer Customer Cases " introduce delay to a DHCP server in the product deployment".
