How to Catch when Proxies Lie
Zachary Weinberg, Shinyoung Cho, Nicolas Christin, Vyas Sekar, Phillipa Gill · 2018
Internet users worldwide rely on commercial network proxies both to conceal their true location and identity, and to control their apparent location. Their reasons range from mundane to security-critical. Proxy operators offer no proof that their advertised server locations are accurate. IP-to-location databases tend to agree with the advertised locations, but there have been many reports of serious errors in such databases.