In this episode of PING, Dr Romain Fontugne, the deputy director of research at IIJ Labs in Tokyo discusses the IIJ "Internet Health Report" and AS Hegemony (or network centrality) in particular.

This is a data model they have been working on for some time (6 years now) which exposes dependencies between ASs in BGP, both directly (as in customer-cone) and indirectly through transitive dependencies. It's a fascinating insight into how BGP dependencies can be seen through the state of the routing table worldwide, and how IIJ are helping BGP speakers understand the dependencies in the transit paths they use. It's also a fertile space for student engagement with google summer of code opportunities.

You can read more about AS Hegemony on the APNIC blog, as well as other posts Romain has made reflecting IIJ's research.

• AS hegemony: measuring AS interdependence (2018)
• BGP zombies (2019)
• The impact of COVID-19 on last-mile latency (2020)

IIJ's Internet Health Report (IHR) is reachable at http://ihr.iijlab.net