SD-WAN is an acronym for software-defined networking in a wide area network (WAN). SD-WAN simplifies the management and operation of a WAN by decoupling the networking hardware from its control mechanism. This concept is like how software-defined networking implements virtualization technology to improve data center management and operation.
A key application of SD-WAN is to allow companies to build higher-performance WANs using lower-cost and commercially available Internet access, enabling businesses to replace more expensive private WAN connection technologies partially or wholly such as MPLS.
American marketing research firm Gartner predicted in 2018 that by 2023 more than 90 percent of WAN edge infrastructure refresh initiatives will be based on virtualized customer premises equipment (vCPE) platforms or SD-WAN software/appliances.