At first, I was contacted by HR for brief simple call, what I am doing, how long, about my carrier etc. On next scheduled session, I was interviewed by company senior engineers. They were mostly asking for troubleshooting part of WAN, BGP, LAN, VRRP, GLBP, HSRP, differences between them, ethernet, portchannel, CPU utilization, network slowness, application slowness, ISO/OSI (L1,2,3) and other incidents that can happend in LAN/WAN. Even I did not passed the interview, I enjoy it. Good luck :)