Chapter 13. Hybrid SDN

It seems that software defined networking is on every network engineer's mind these days, and rightfully so. Ever since the introduction of OpenFlow in 2010, we have seen steady news on traditional networks transition to a software-defined network. The news typically focuses on the infrastructure agility as competitive advantage that the change brings. Many high profile SDN startups were formed offering new network services, such as SD-WAN. In the slower paced standards bodies, SDN standards were gradually being ratified. In the marketplace, vendors such as Quanta and Pica8 started to join forces in making carrier-grade hardware that was de-coupled from software. The combination of results is a seemingly new SDN world, just waiting around the corner for all networks to transition to. However, the reality is a bit different. Despite all the progress SDN have made, the technology deployment seems to be biased toward the very large, some might call Hyperscale, networks...