Architecture of a Cloud-based Fault-Tolerant Control Platform for improving the QoS of Social Multimedia Applications on SD-WAN

Social media application are becoming multimedia centric with live and stored video, audio, augmented reality, haptic, etc. emerging as the main categories of traffic. Their QoS requirements are more stringent than their legacy counterparts. At the carrier level, Software Defined - Wide Area Network (SD-WAN) is one of the promising technologies for transporting these multimedia traffic. A SD-WAN will typically have a mesh of centralized controllers managing the networking infrastructure. Reliable operations of these controllers are a key requirement for the successful operation of the WAN. Controller failure will prevent the forwarding switches from communicating with the controller. This will prevent the switches from forwarding any new traffic, as well as flow entries from existing traffic will also time out after a period bringing the network to a standstill. Rebooting a controller or starting a new one will introduce delays degrading the QoS. This research presents an architecture for handling controller failure via transparent migration of the controller load in a semi-meshed controller environment. The architecture includes a real time cloud-based centralized storage of the flow states north of the controllers and a virtualized connection management unit at the south. The results demonstrate that the proposed model can transparently handle controller failure without affecting the QoS.