How does uptime relate to SD-WAN performance targets?

• A. Uptime targets specify availability, often expressed as a percentage.
• B. Uptime is not related to performance targets.
• C. Uptime measures only the capacity of the cloud link.
• D. Uptime is equivalent to MTTR only.

Answer: (A)

Uptime targets define how available the network and services should be, expressed as a percentage over a given period. In SD-WAN, this matters because the technology relies on multiple paths and dynamic rerouting to keep applications reachable. A target like 99.9% uptime means only about 8.77 hours of downtime per year, guiding design decisions for redundancy, failover, and monitoring to maintain that level of availability. It’s not about how much capacity a single link has, nor is it the same as MTTR (the time to repair a fault). Uptime directly measures the proportion of time services are accessible, making it the most accurate way to express performance targets for reliability.