Software defined networking (SDN) is one of the key technologies driving the transformation of the next generation networks. To begin with, SDN was just a mechanism to “separate out control from data”. The logic to control the network was moved to a centralized controller. This allowed the operators to program the network on demand, from one point of control. Further, it allowed them to set rules/configurations across devices, from different vendors in a unified way, without manual intervention. These flexibilities proved to be a huge improvement over traditional networking where provisioning/configuration was done on individual basis and a single failure in the network could lead to huge downtimes. The notion and scope of SDN applicability in networks has considerably transformed since then. Traditional networking using distributed routing protocols are focussed on the needs of the basic network; route discovery, link failure recovery, etc. However, these services by themselves don’t fulfil the requirements of emerging technologies like IoT and MEC – handling multi-vendor devices, heterogenous networks (Wi-Fi, Bluetooth, ZigBee, LTE), huge amount of data, faster deployments, management of services etc. SDN promises to deliver an agile and flexible network infrastructure, to handle varying user-demands and diverse network scenarios.