Modern critical operations and defence applications require highly demanding information and communication systems, making ad hoc networks, which are mainly used nowadays in tactical zones, to be difficult to manage. The evolution of the Software Defined Networking (SDN) technology has brought new perspectives to security and defence applications, making them more reliable, more stable, more secure and more portable. This research paper proposes an SDN topology for secure communications in a tactical environment, overcoming several challenges that a conventional network faces. Moreover, an Artificial Intelligence (AI) methodology, exclusively used in SDN environments is presented, providing Quality of Service (QoS) features to the network, based on which rerouting paths can be calculated. Finally, our routing methodology is illustrated using representative evaluation scenarios.