Abstract: In this talk, we first present visualizations of how CENIC networks --- CalREN-DC, CalREN-HPR and CalREN-XR --- connect to the Internet using BGP. We also show examples of how customers can reach the outside world and each other via CENIC networks in a number of ways. The visualizations abstract away physical equipments and links and focus on routing. We discuss the interactions between CENIC and its customers, in terms of routing and routing policies configured in CENIC networks and inside the customers. To study BGP dynamics, we apply analysis techniques to routing data collected at CENIC and a customer network. We observe some unusual incidents, and compare them seen from the different network viewpoints.

Abstract: In today's internet, BGP is extremely chatty --- the most minor connectivity change produces hundreds of updates and a significant peering loss can generate millions. While gigahertz processors and terabyte disks have made it possible to capture and record BGP events via passive peering, making sense of the deluge of data remains difficult.

We have developed statistical algorithms to extract the large-scale structure of BGP event streams and visualization techniques to display that structure in operationally meaningful ways, i.e., to quickly answer questions like "what happened?", "where did it happen?" and "how does it affect me?." These tools can also be used to provide real-time views of an ISP's interdomain topology that help rapidly diagnose problems like misconfigured community tags, policy filters with unintended consequences, unexpected or unwanted backup paths, peering traffic imbalance, etc.

The analysis is fast enough to run in real time on a modern processor even when dealing with, for example, the entire backbone mesh of a typical tier-1 ISP. We will describe the algorithms and show case studies from variety of data taken on both large ISP backbones and large institutional networks.

(Here is the accompanying paper.)