A Northbound API for QoS Management in Real-Time Interactive Applications on Software-Defined Networks

—Real-Time Online Interactive Applications (ROIA), e.g., multiplayer online games and simulation-based e-learning, make high Quality of Service (QoS) demands on the underlying network. These demands depend on the number of users and the actual application state and, therefore, vary at runtime. Traditional networks have very limited possibilities of influencing the network behavior to meet the dynamic QoS demands, such that most ROIA use the underlying network on a best-effort basis. The emerging Software-Defined Networking (SDN) technology decouples the control and forwarding logic from the network infrastructure, making the network behavior programmable for applications. This paper analyses ROIA requirements on the underlying network and describes the specification and design of an SDN Northbound API that allows ROIA applications to specify their dynamic network requirements and to meet them at runtime using SDN networks.