You are redesigning a single-level IS-IS network with 500 routers, which have short-haul and long-haul links Most of the time the routing domain is stable, but periodically interfaces on long-haul links bounce for a short period of time , causing 10 to 20 flaps in a few minutes. The probable cause is local road construction. Although fast convergence important, the client has concerns about taxing CPU cycles on the older routing platforms. What change should you recommend that both protects the CPU of the older routers during the short periods of excessive flapping, yet does not have an impact on fast convergence for all interface failures?