Mitigating Satellite Link Variability in SD-WAN using Constellation-Aware Edge Routing

Low Earth Orbit (LEO) satellite constellations are rapidly expanding global Internet access, offering increasingly cost-effective connectivity. Compared to geostationary systems, LEO networks provide the potential for significantly higher bandwidth and lower latency, making them technologically attractive. This performance potential, combined with ubiquitous coverage extending to remote and underserved areas, positions LEO as a compelling underlay technology for Software-Defined Wide Area Networks (SD-WAN), promising enhanced enterprise connectivity. However, recent network measurements have highlighted a critical challenge: LEO's highly dynamic topology induces significant latency variability and packet reordering, straining traditional reactive SD-WAN path selection mechanisms and impacting applications with strict performance requirements. To unlock LEO's full potential for SD-WAN, we propose a novel Constellation-Aware architecture. Our approach embeds a lightweight predictive satellite simulator within the edge Customer Premises Equipment (CPE). By leveraging ephemeris data to anticipate path changes and predict delay variations, the system enables proactive routing insights, allowing traffic steering before significant degradation occurs. This edge-centric design mitigates LEO link variability, enhancing SD-WAN reliability over satellite without requiring satellite network modifications.