Inferring Country-Level Transit Influence of Autonomous Systems

We tackle the problem of identifying the most influential transit providers in each country that may have the potential to observe, manipulate or disrupt Internet traffic flowing towards that country. We develop two new Internet cartography metrics to overcome several challenges with making such inferences using BGP data. The transit influence (TI) metric estimates the share of addresses of an origin AS served by the transit AS. The Aggregate Transit Influence (ATI) captures the aggregate of all fractions of each country’s origin ASes’ addresses that the transit AS serves. We apply these two metrics to identify the most influential ASes in each country, and the origin ASes in those countries that heavily depend on transit ASes. We include extended case studies of the transit ecosystems of countries in Latin America, Africa and Europe, and we also investigate the role of state-owned ASes in the Internet ecosystem of their home country and in foreign countries. We believe these metrics advance our ability to characterize structural weaknesses in the global Internet topology.