In SD-WAN terminology, what is the difference between a tunnel and a path?

• A. A tunnel is the end-to-end route for an application across one or more tunnels/underlays.
• B. A tunnel is only used for control-plane traffic; a path carries user data.
• C. A tunnel is the encrypted/encapsulated link between endpoints; a path is the end-to-end route for an application across one or more tunnels/underlays.
• D. A path is always a single tunnel; a tunnel can be multipath.

Answer: (C)

In SD-WAN, a tunnel is the encrypted/encapsulated link between two edge devices. It creates a secure transport channel over the underlying network. A path, by contrast, is the end-to-end route that an application’s traffic takes from source to destination, which may traverse one or more tunnels and/or underlays. This distinction lets you have multiple tunnels (over different providers or networks) between sites, while the path determines which tunnel(s) to use for a given application to reach its destination, enabling policy-driven routing and resilience.