What is Forwarding Plane

Networking has seen a burst of innovation and rapid changes with the advent of Software Defined Networking (SDN). Many people considered SDN to be something new and innovative, but actually SDN is something that has already been proposed almost a decade ago in the era of active and programmable networks, and developed even before that. Coupled with the fact that SDN is a very dynamic area with everyone trying to brand their architecture, research or product as SDN has defined a vague and broad definition of what SDN. This chapter attempts to put SDN into perspective approaching SDN with a more spherical point of view by providing the necessary background of pre-SDN technologies and how SDN came about. Followed by discussion on what SDN means today, what SDN is comprised of and a vision of how SDN will evolve in the future to provide the programmable networks that researchers and operators have longed for for many years now. This chapter closes with a few applicability use cases of the future SDN and wraps up with how SDN fits in the Future Internet Architectures.