[cjbprime]

Would be interesting to see a link! That doesn't sound like it would get an accurate guess to me, given facts like "light travels slower in copper than fiber" and "your packets have to enter a country through specific large hubs" etc etc.

[Avamander]

If you have enough machines you can just use machines after those large hubs. The copper/glass light speed difference doesn't matter much because the speed differences added by hops in the middle are usually orders of magnitudes higher.

In the end, unless you've got machines next door pinging your target you won't be able to differentiate between houses or city blocks.