Which statement correctly describes Bidirectional Forwarding Detection (BFD)?
- BFD replaces routing protocol hello mechanisms completely
- BFD is only supported with OSPF and BGP
- BFD provides fast failure detection independent of routing protocols
- BFD requires hardware support and cannot run in software
Explanation: According to the sources, Bidirectional Forwarding Detection (BFD) provides fast peer failure detection times independently of all media types, encapsulations, topologies, and routing protocols such as BGP, EIGRP, IS-IS, and OSPF.
It is a low-overhead, short-duration method designed to detect failures in the forwarding path between adjacent routers at a uniform rate, rather than the variable rates used by different routing protocol hello mechanisms.
While BFD relies on the routing protocol for neighbor discovery, it functions as a generic and consistent failure detection mechanism that can notify the control plane to initiate recalculation and reduce overall network convergence time to less than one second.
Related exam: CCNP ENARSI v9 Course Final Exam
