Refer to the exhibit. You are asked to design this OSPF network to converge within 60 ms for unicast packets after a topology change due to a single link failure. Which technology can be enabled while

LFA (RFC 5286) pre-computes alternate next-hops during normal SPF operation and installs them in the FIB alongside primary routes. When a link fails, the router immediately switches to the pre-installed backup next-hop without running a new SPF, achieving failover times well within the 60ms design requirement.

BFD rapidly detects link failures but does not itself provide alternate forwarding paths - the router still requires SPF recalculation after BFD detection, which can exceed 60ms.

Tuning IGP hello and dead timers reduces failure detection time but convergence still depends on SPF execution, making consistent sub-60ms convergence difficult to guarantee.

SPF timer tuning reduces SPF scheduling delay but does not eliminate the SPF recalculation step after a failure, and reliably achieving sub-60ms convergence through SPF tuning alone is not practical.

RSVP-TE Fast Reroute can achieve 50ms reroute but requires full MPLS Traffic Engineering infrastructure, which is not indicated as present in this plain OSPF network design.