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Calls across networks (TURN)

Calls connect directly between devices. When both people are behind strict NATs (mobile data, office networks), a direct connection isn’t possible, so a TURN relay forwards the encrypted media. Without one, such calls ring and “connect” but carry no sound or video.

  • Methods 2/3: answer yes when the installer asks about a TURN relay (or pass --turn). It installs coturn, opens its ports and fills in TURN_URLS / TURN_SECRET. Also open ports 3478, 5349 and 49160–49200/udp in your hosting provider’s firewall.
  • Docker, or a relay on another machine (for example eturnal, which also runs on Windows): set TURN_URLS (or TURN_EXTRA_URLS) and TURN_SECRET to the relay’s address and shared secret.

The relay only ever sees encrypted call traffic. More in deploy/INSTALL.md.