libzt

e lower than about 1/2 the time it takes a photon to travel the Earth's diameter. In practice it's higher since you must also account for median router latency. Same goes for high throughput though in that case you need much more detailed intel on the physical network. Rule of thumb here: if throughput is higher than global mean it can be used to rule out and thus narrow down paths in the graph. ZeroTier provides fast efficient low-latency direct connectivity but to do this requires that it introduce people directly, thus revealing peoples' locations (IP-wise) to each other. This is a hard requirement since the most efficient path is by definition the most direct and therefore de-anonymized (again IP-wise) path. You can't go directly A<>B without A knowing where B is and vice versa. Edit: I speak a bit theoretically above. In practice a weaker anonymity system could be deployed closer to the last mile to hide people at e.g. city resolution. But AFIAK this is not what Tor does, would probably require either a huge critical mass or last-mile carrier participation or both, and would still have a performance impact.