Tailscale

An engineer traveling from the US to India found direct Tailscale connections failed due to symmetric CGNAT on Indian ISPs, forcing traffic through shared DERP relays throttled to ~2.2 Mbits/sec. Self-hosted Tailscale Peer Relays (a node with an open UDP port) restored 27-35 Mbits/sec and cut latency ~150ms by removing the Chicago relay hop. The article explains NAT diagnosis tools and relay setup; DERP remains the fallback, and the tradeoff is operating and exposing a relay on your own infrastructure.