Making Route Flap Damping Usable
Internet Initiative Japan
Cisco Systems
Cisco Systems
Internet Initiative Japan
Route Flap Damping (RFD) was first proposed to reduce BGP churn in routers. Unfortunately, RFD was found to severely penalize sites for being well-connected because topological richness amplifies the number of update messages exchanged. Many operators have turned RFD off. Based on experimental measurement, this document recommends adjusting a few RFD algorithmic constants and limits, to reduce the high risks with RFD, with the result being damping a non-trivial amount of long term churn without penalizing well-behaved prefixes' normal convergence process.