I was speaking with a participant of the recent SDN event in Zurich after the presentations, and he made an interesting comment: whenever he experienced serious troubleshooting problems in his career, it was due to lack of understanding of networking fundamentals.
Let me give you a few examples: Do you know how ARP works? What is proxy ARP? How does TCP offload work and why is it useful? What is an Ethernet collision and when would you see one? Why do we need MLD in IPv6 neighbor discovery?
Networking is already commoditized enough that most engineers never truly master the fundamentals (it's one thing to hear about ARP in a CCNA class and completely another one to troubleshoot an interesting proxy ARP problem caused by overlapping subnets), but it's only getting worse.
In the SDN world, the networking infrastructure will become ever more complex, and you'll experience totally unexpected interactions between controllers, controlled network devices, and attached end hosts. The deep understanding of the fundamentals will be the only way to ensure you'll successfully fix problems in your SDN networks, regardless of the clueless marketing VPs telling you how we no longer need networking engineers.
The lack of understanding of technology fundamentals, and their impact on solutions we're trying to deploy in our networks was one of the primary reasons I started creating ipSpace.net webinars. Have you tried the free introduction to SDN? Did it work for you? Need more details? Check out the advanced SDN track, or get access to all ipSpace.net webinars with the yearly subscription.