We have discovered a problem with the BGP decision algorithm that can led to an endless BGP convergence loop in certain topologies. So far, we know of two different types of "The Churn." Type I occurs in networks that have a single tier of RRs or confederation Sub-ASs (please see http://www.cisco.com/warp/public/770/fn12942.html for more details). Type II churn occurs in a network that has more than one tier of RRs or confederations. Currently there is not a solution for Type II churn, but we are working on a change to the BGP spec that will fix this problem.

About the Presenter
Daniel is currently on the Routing Protocols Deployment and Scalability team at Cisco, where he concentrates on BGP and ISIS. Previously, he worked in the Cisco TAC and ISP Expert team, where he focused on BGP and other routing protocols.