A Comprehensive Survey on Software-Defined Wide Area Network

The rise of Software-defined wide area network (SD-WAN) a decade ago has ushered in a new era of networking opportunities for organizations worldwide. As enterprises undergo digital transformation fueled by cloud computing adoption and the imperative for enhanced connectivity, SD-WAN has emerged as a transformative paradigm. This survey paper unpacks the intricate ecosystem of SD-WAN technology, offering a deep dive into its foundational principles, architectural components, and diverse deployment scenarios. We explore modern SD-WAN architectures, analyzing key elements such as customer premises equipment (CPE), underlay and overlay networks, controllers, and orchestration planes. By shedding light on the mechanisms that drive SD-WAN’s agility and efficiency, we provide critical insights into its transformative potential. Beyond architecture, we examine essential operational aspects, including traffic engineering, performance monitoring, and network resources management within the SD-WAN framework. We also identify key challenges and research gaps, charting a path for future advancements in the field. This comprehensive study serves as a valuable resource for academics, researchers, and industry professionals navigating the evolving landscape of enterprise networking in the era of cloud-driven digital transformation.