Network-Coded SD-WAN in Multi-Access Systems for Delay Control

An industrial IoT network may involve hundreds of IoT end-devices deployed over large geographical wide areas networks (WAN). These devices are expected to operate over several years and their individual communication interface may be gradually upgraded with multiple communication links in order to fit the changing application and data rate requirement. As industrial networks are expected to perform with high reliability and availability, a continuous monitoring and maintenance of these communication links is essential. A software defined WAN (SD-WAN) based solution allows to adaptively monitor and manage the connectivity links as per the application requirement. In this paper we design and implement a working SD-WAN based multi-access system for upstream communication between an IoT device and the control center. Each IoT device may have multiple cellular interfaces, and we control the end-to-end delay jitter variation across the different interfaces via an intelligent traffic splitting scheme.We provide an analysis of end-to-end delay jitter under LTEs uplink connection and use the structural results so obtained to design a traffic split mechanism. We validate our analysis, and provide traffic split performance results from our working multi-access system.