On 26 Aug 2000, Sean Donelan wrote: :Have any providers done a formal study of how many points they share :in common with other networks? I know most providers consider their :competition, if nothing else for how peering will be done. There :seems to be a tremendous amount of overlap between networks. Almost :every major network map looks identical. And there are some third-party :consultants selling network maps. But I was wondering if anyone had :a formal study from "the horses mouth." I missed the discussion from a few weeks ago, but is this for physical network maps? If not, couldn't this be done using routing tables, RAdb information, and some geometry a la CAIDA? Aren't most accurate physical network maps borderline classified for the most part? Many network maps include a PVC they use from a Tier-1 provider as part of a 'physical' infrastructure, which would cause their network map to be conspicuously similar to that of their transit provider. CAIDA's AS connectivity maps are the closest thing to a study that I have seen. -j