This White Paper reviews the current state of enterprise WAN usage, key challenges businesses face today with their WAN, the impact of digital transformation initiatives on the WAN, and key benefits of using software-defined WAN (SD-WAN). The ideas presented in this White Paper draw on the findings of a March 2017 survey of more than 800 network management executives about WAN usage and attitudes. The survey was conducted by IDC and sponsored by Comcast Business.