A network engineer must select a high availability feature for their data center. The solution must ensure network resilience, reduce network instability for Layer 3 routing protocols, and meet these

BFD (Bidirectional Forwarding Detection) is a fast detection protocol for link failures, but it does not address control plane restart or stateful switchover requirements for suppressing routing flaps.

HSRP (Hot Standby Router Protocol) provides first-hop redundancy for end devices but does not address control plane restarts, routing protocol stability, or stateful switchovers on the routing device itself.

Non-Stop Forwarding (NSF) with Stateful Switchover (SSO) is a high availability feature that allows a router to continue forwarding data packets even when its control plane is restarting or performing a switchover. It maintains forwarding information and notifies neighbor routers via graceful restart mechanisms, preventing routing flaps and ensuring network stability.

ISSU (In-Service Software Upgrade) allows for software upgrades without service disruption but is not a general high availability feature for control plane restarts and routing protocol stability in the same way NSF is.