Which Cisco SD-WAN protocol detects WAN path liveliness and measures latency, jitter, and packet loss?

Which Cisco SD-WAN protocol detects WAN path liveliness and measures latency, jitter, and packet loss?

• A. BFD
• B. CDP
• C. STP
• D. LACP

Answer: (A)

Bidirectional Forwarding Detection is designed to rapidly verify the health of a WAN path between SD-WAN devices. It exchanges small control packets at frequent intervals, so if responses stop or timing exceeds a threshold, the path is considered failed and traffic can be quickly rerouted. It also provides timing information that can be used to gauge latency, jitter, and packet loss on the path, which helps the SD-WAN controller choose the best routes. The other protocols serve different purposes: CDP is for neighbor discovery, STP prevents switching loops, and LACP aggregates links but does not monitor WAN path liveliness or measure these performance metrics.

Bidirectional Forwarding Detection is designed to rapidly verify the health of a WAN path between SD-WAN devices. It exchanges small control packets at frequent intervals, so if responses stop or timing exceeds a threshold, the path is considered failed and traffic can be quickly rerouted. It also provides timing information that can be used to gauge latency, jitter, and packet loss on the path, which helps the SD-WAN controller choose the best routes. The other protocols serve different purposes: CDP is for neighbor discovery, STP prevents switching loops, and LACP aggregates links but does not monitor WAN path liveliness or measure these performance metrics.