Here is your peer! — Locating peers on a regional level with network coordinates

It seems to be common wisdom that peer-to-peer overlay networks should reflect the structure of the underlying network to minimize the application-level latency, to increase the throughput, and to optimize the traffic for the Internet service providers. Network coordinates are one means to achieve this goal. However, previous real-world experiments were disappointing because methods like Vivaldi could not resolve the structure of the underlying network better than at a continental level. In our work, we have closely analyzed the reasons for that disappointing performance. Thereby, we were able to improve Vivaldi-like network coordinate systems so that they can now differentiate peers at a regional level. In this paper, we report on a large measurement study that we performed with the Vuze BitTorrent client. We show that these improved algorithms can indeed differentiate among different autonomous systems and different geographic regions. We also show that this achievement is less important than commonly thought and that the key contribution lies rather in the latency-optimal overlay formation itself.