Characterization of BGP Recovery Time under Large-Scale Failures

Border gateway protocol (BGP) is the standard routing protocol between various autonomous systems (AS) in the Internet. In the event of a failure, BGP may repeatedly withdraw some routes and advertise new ones until a stable state is reached. It is known that the corresponding recovery time could stretch into hundreds of seconds or more for isolated Internet outages and lead to high packet drop rates. In this paper we characterize BGP recovery time under large-scale failure scenarios, perhaps those caused by disastrous natural or man-made events. We show that the recovery time depends on a variety of topological parameters and can be substantial for massive failures. The study provides guidelines on reducing the impact of BGP convergence delay on the Internet.