What does path reliability mean in SD-WAN performance metrics?

• A. The color of the path's label.
• B. The number of hops only.
• C. The MTU value.
• D. The likelihood that a given path remains usable with low loss and latency.

Answer: (D)

Path reliability in SD-WAN performance metrics measures how consistently a path can carry traffic with acceptable loss and latency—that is, how likely it is to remain usable without degrading application performance. This concept matters because SD-WAN often uses multiple transport paths and dynamically steers traffic based on how robust each path is over time. A path with high reliability will regularly deliver packets within the required latency and with minimal losses, making it a preferred route for critical traffic.

Why this best describes the idea: reliability isn’t about visual attributes like a path’s label color, nor about simply counting hops. It also isn’t about the MTU, which affects maximum packet size, not the ongoing ability to deliver traffic within SLA thresholds. Instead, reliability captures the consistency of performance—low loss and low latency over time—so the network can maintain stable service levels even as conditions change.