Software defined network (SDN) is the revolutionary technology in the Networking atmosphere. It finds its roots in programmable network and control-data-infrastructure plane separation which provides network management as well as network automation. This technology encourages programmability of the network which in turns reduces the cost of operation and increases efficiency. The objective of this paper is to study the various investigations going to understand and evaluate SDN characteristics and benefits. In this paper we will be exploring SDN architecture, SDN related taxonomy and challenges SDN implementation face now and in future. © 2016, International Journal of Pharmacy and Technology. All rights reserved.