The marriage of software-defined networking (SDN) with wide area network (WAN) technology enables efficient management of complex diverse deployments through the use of common virtual private network (VPN) capabilities and the separation of data and control planes within SDN. With SD-WAN, software-managed connections can be established and managed between multiple sites over any number of link types (e.g., fixed circuit, DSL, cable, mobile, MPLS, and so on) without the operational challenges of having to manage different links. SD-WANs manage traffic according to application or service requirements (e.g., VoIP vs. Facebook), and enforce policy control capabilities (e.g., limit web-based traffic to 50% of a given link). SD-WAN options are part router, part WAN optimization and traffic shaping, part access control, and part VPN. In addition, some SD-WAN offerings provide robust security, which makes for a compelling alternative to the multiple-appliance approach that is often required at remote locations.

This Test Methodology describes how NSS Labs will evaluate SD-WAN solutions to provide an objective and fair assessment of the technology.