A software-defined wide area network(SD-WAN)is a wide area network that uses software defined network technology,such as communicating over the Internet using overlay(69)which are encrypted when destined for internal organization locations.SD-WAN simplifies the management and operation of a VAN by decoupling the networking hardware from its(10)mechanism.This concept is similar to how software-defined networking.Implements(71)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(72)access,enabling businesses to partially or wholly replace more expensive private WAN connection technologies.SD-WAN technology supports(73)of Service(QoE)by having application-level awareness,giving bandwidth priority to the most critical applications.此题为第72问