The road to SDN

TLDR

Software‑Defined Networking (SDN) is a programmable networking paradigm that builds on a long history of efforts to separate control and data planes, enabling innovative network design and management. This paper traces the intellectual evolution of programmable networks, from early active networks to modern OpenFlow and network operating systems. The authors highlight key concepts and the technology pushes and application pulls that drove each innovation. They debunk common myths and clarify the relationship between SDN and related technologies such as network virtualization.

Abstract

Software Defined Networking (SDN) is an exciting technology that enables innovation in how we design and manage networks. Although this technology seems to have appeared suddenly, SDN is part of a long history of efforts to make computer networks more programmable. In this paper, we trace the intellectual history of programmable networks, including active networks, early efforts to separate the control and data plane, and more recent work on OpenFlow and network operating systems. We highlight key concepts, as well as the technology pushes and application pulls that spurred each innovation. Along the way, we debunk common myths and misconceptions about the technologies and clarify the relationship between SDN and related technologies such as network virtualization.