Which Cisco SD-WAN feature continuously measures latency, loss, and jitter across WAN transports?

• A. BFD monitoring
• B. DHCP snooping
• C. STP optimization
• D. HSRP tracking

Answer: (A)

Continuous transport health monitoring in Cisco SD-WAN is achieved with BFD monitoring, which continuously measures latency, loss, and jitter across WAN transports by exchanging small, fast-control packets between SD-WAN edge devices. This rapid feedback provides up-to-date per-transport performance data, allowing the SD-WAN controller to select the best path and quickly fail over when a link degrades. Other options focus on security (DHCP snooping), loop prevention and bridging (STP), or gateway failover (HSRP tracking) and do not offer ongoing, per-transport performance measurements across multiple WAN links.