Future SDN-Based Network Architectures

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. INTRODUCTION AND HISTORICAL BACKGROUND TO SDN Network research has gained a burst of activity and innovation for the past couple of years, with the advent of what is called, Software Defined Networking (SDN). SDN, as a term, was introduced in 2008 by Stanford University researchers (McKeown et al. 2008) as an attempt to enable researchers to operate network in a more programmable fashion in order to run their experiments such as new protocols, interfaces or algorithms on real production networks. Evangelos Haleplidis University of Patras, Greece Spyros Denazis University of Patras, Greece Odysseas Koufopavlou University of Patras, Greece