What does door-to-door measurement mean in SD-WAN performance assessment?

• A. End-to-end measurement across all network segments from source to destination.
• B. Measuring only at the customer's premise.
• C. Only within the data center.
• D. Only at the cloud provider's edge.

Answer: (A)

Door-to-door measurement means evaluating performance from the source all the way to the final destination, across every network segment the traffic traverses. In SD-WAN, this end-to-end view covers the entire path—from the user’s device at the premises, through the WAN transport, across any public internet segments, to the remote site, data center, or cloud edge. This holistic view is crucial because a bottleneck or loss could occur on any part of the route, and only measuring the whole journey reveals the true user experience. If you only measure at the customer premise, you miss the rest of the path; if you measure only inside a data center or only at the cloud edge, you miss the WAN and internet segments in between. Thus, door-to-door measurement is end-to-end across all network segments.