The integration of thriving information and communications technology (ICT) and cyber-physical systems (CPSs) has spawned several innovative applications, such as remote healthcare, smart and intelligent transportation, smart logistics, smart grids, and public safety. An emerging software-defined networks (SDNs) technology further enabled to optimize the communication among Industrial IoT (IIoT) and CPS entities. Nonetheless, the communication on public channel among different IIoT entities in an SDN-enabled environment may be exposed to various security threats due to wireless and insecure communication channels. To counter these security challenges in the way of wider CPS or IIoT adoption, we propose a novel three-factor authenticated key exchange mechanism (SUSIC) for SDN-enabled IIoT ecosystem. The SUSIC enables a registered user to access real-time data from physical IIoT environment directly after having mutual authentication performed through SDN-enabled controller node. The scheme is proved to be secure under rigorous formal and informal security analysis. Moreover, the simulation results and performance evaluation signifies toward achieving a better tradeoff between security functionalities and computational overheads comparatively.