Locating BGP missing routes using multiple perspectives
Di-Fa Chang, Ramesh Govindan, John Heidemann · 2004
There have been many studies on measuring and interpreting inter-domain routing dynamics. Most of them, however, are based on the approach of off-line and passive post-processing BGP routing updates. We propose a new methodology that uses real-time and active monitoring to troubleshoot various BGP routing anomalies. This paper focuses on a specific BGP routing problem -- missing routes that occur when some ASes can reach a prefix while others can't. The idea is to periodically monitor the BGP routing status at multiple vantage points, like Route Views, and when a possible missing route event is detected issue traceroute queries from various looking glasses to learn of the packet-forwarding path status. By comparing previous and current packet-forwarding paths, we can have an idea of where the missing route event takes place. This paper examines the plausibility of this methodology and discusses preliminary experimental results.