I've been conducting interviews over the past 6 years and I've done probably hundreds of technical phone screening, on-site whiteboard sessions. I always make sure I ask questions on topics that are typically considered as core network fundamentals and I do that for two reasons. If the role is for a senior network engineer/architect, I want to confirm that the basics are not overlooked when I give the candidate a design or troubleshooting scenario. If the role is for a more of a junior level network engineer, I want to make sure that the candidate has a solid understanding of the fundamental network concepts. I'm a firm believer that solid understanding of the network fundamentals is key for any network