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Comment by raggi

4 days ago

Tailscale uses latency to pick home DERPs and I am re-evaluating it as we observe what appear to be manipulated STUN latencies for users in Asia particularly in or close to China. The latencies are often raised to over 300ms to affect this, and steer clients toward the US west coast. The reason for these manipulations is unclear, but it's easy to speculate.

> The reason for these manipulations is unclear, but it's easy to speculate.

Care to elaborate? I don’t know why anyone would do this.

  • This is tin-foil-hat speculation, but for example, if you observe a locality measurement protocol picking where it should connect to, but you already know all of the local sites of interest that are relevant, you might want to find remote sites of interest. If you manipulate the more open sampling protocol to lean toward that remote site, you can then observe where secured connections to which you're otherwise blind, connect to. Now you have new remote targets of interest.