Towards Adaptive QoS in SDN-enabled Heterogeneous Tactical Networks

This paper introduces a mechanism to adaptively ensure Quality of Service (QoS) for user data flow by leveraging Software-Defined Networking (SDN) in heterogeneous tactical networks. We start with a hypothesis that an application using the northbound interface of the SDN controller can support the management of unreliable radio links at the edge of tactical networks. Thus, we developed applications to support adaptive shaping of user data flows over data rates supported by VHF and UHF radios, and to ensure the dropping of expired messages. We also introduce a hybrid scheduling mechanism for these user data flows using queuing discipline. The goal is to differentiate IP packets from command and control services with different QoS requirements. Our hypothesis was verified with experiments using four classes of messages with different QoS requirements, such as priority, reliability, and time of expire. Experimental results in an emulated network suggest that our solution can differentiate data flows in a heterogeneous tactical network while ensuring its QoS requirements.