> > How much of this research is based on marketing maps on the ISPs' web sites, > > versus actual maps of the networks in question? Most "tier 1" ISPs won't > > even let their vendors see the latter.
> last year we *measured* isp maps as part of a research project called > rocketfuel and found that the marketing maps can differ significantly from > the real ones quite a bit because of lack-of-detail, outdated-ness, or > optimistic-projections. a paper describing the methodology and the maps > themselves can be found off: > http://www.cs.washington.edu/research/networking/rocketfuel/ Something is wrong here... You are claiming that your maps are *MORE* correct than the ISP maps!? I don't think so. I had a look at your map of Ebone Europe through the browse button on your website. This displayed a messy meshy network that connected all the major cities of Europe. However, in fact, Ebone's network was a nice clean ringed network connecting all the major cities of Europe. It's true that Ebone's marketing map had some innacuracies but it still more or less showed the same network of sub-rings hanging off of a core ring. I just don't see how an outside probe can determine the true topology of a network. If a researcher wants to do analysis of real network topologies they either need to get the real maps from the ISPs in question or else they need to ally themselves with someone like Telegeography who have this information for at least some ISPs. --Michael Dillon