Which of the following is a primary function of the SD-WAN Edge device?

• A. Terminates underlay connections, establishes tunnels to other edges or the orchestrator, enforces local policies, applies QoS, and provides security services.
• B. Acts as a central policy controller for the entire fabric.
• C. Serves as an external firewall only for the data center.
• D. Implements only DNS resolution for the network.

Answer: (A)

The SD-WAN Edge is the site’s data-plane gateway that binds the local underlay to the SD-WAN overlay. It terminates the physical transports at the site, establishes and maintains tunnels to other Edges or to the central orchestrator, and then uses those tunnels to carry traffic across the fabric. Beyond just connectivity, it applies policies locally, enforces QoS to prioritize critical traffic, and provides security services like encryption and firewalling at the edge. This combination of terminating underlay, forming tunnels, and enforcing site-level policies and protections is exactly what the Edge is built to do.

The central policy controller (orchestrator) is a separate role that pushes fabric-wide policies and coordinates behavior across Edges, rather than being the device that terminates underlay or enforces local traffic policies itself. Describing the Edge as only a firewall for the data center or as performing only DNS resolution misses the core data-plane and policy-enforcement responsibilities that define the Edge’s primary function.