In this post, David Varnum goes over some of the fundamental concepts of OpenFlow. He goes as far back as to distinguish the control plane from the data plane. David then goes into great detail about OpenFlow’s design and features. What inspired this deep dive into OpenFlow? At Networking Field Day in November, David saw a presentation from NEC on their ProgrammableFlow controller, a SDN product that uses the OpenFlow protocol. David found it “wildly impressive”, and wanted to get a better understanding of the protocol.