Based on feedback we have received at http://as-rank.caida.org/ we are in the process of updating our AS relationship inference algorithm. We're interested to know how many providers different ASes have based on their size. We assume that it changes with size of the AS, e.g. Tier-1 have zero. We would appreciate it if anyone who is willing to provide us with their AS number and the number of their providers, would email this information to mjl@caida.org. Matthew Luckie CAIDA. p.s. It would be great if you could also tell us who your providers are.