350-401 Network Assurance Practice Question

Correct answer & explanation

UplinkFast is correct because it enables a switch to immediately use an alternate root port when its current root port fails, bypassing the usual 30-second listening and learning delay. This is achieved by artificially lowering the bridge priority of the switch to trigger a topology change notification, allowing the backup port to transition directly to forwarding. BackboneFast is correct because it reduces convergence time by detecting indirect link failures in the backbone and allowing a switch to expire its Max Age timer (default 20 seconds) immediately, rather than waiting for the full timer to expire, thus speeding up the transition to a new root port.