The software-defined wide-area network (SD-WAN or SDWAN) is a specific application of software-defined networking (SDN) technology applied to WAN connections such as broadband internet, 4G, LTE, or MPLS. It connects enterprise networks — including branch offices and data centers — over large geographic distances.
A WAN might be used, for example, to connect branch offices to a central corporate network, or to connect data centers separated by distance. In the past, WAN connections often used technology that required special proprietary hardware. SD-WAN, on the other hand, utilizes the internet or cloud-native private networks. SD-WAN decouples the network from the management plane and detaches the traffic management and monitoring functions from hardware. It relies on four central components: