Network Heterogeneity and Cascading Failures – An Evaluation for the Case of BGP Vulnerability

Large-scale outages of computer networks, particularly the Internet, can have a significant impact on their users and society in general. There have been a number of theoretical studies of complex network structures that suggest that heterogeneous networks, in terms of node connectivity and load, are more vulnerable to cascading failures than those which are more homogeneous. In this paper, we describe early research into an investigation of whether this thesis holds true for vulnerabilities in the Internet’s inter-domain routing protocol – BGP – in light of different network structures. Specifically, we are investigating the effects of BGP routers creating blackholes – observed phenomena in the Internet in recent years. We describe our evaluation setup, which includes a bespoke topology generator that can fluidly create any topology configuration from the current scale-free AS-level to the investigated homogeneous graphs. We find that network homogeneity as suggested by theory does not protect the overall network from failures in practice, but instead may even be harmful to network operations.