Simple Voice Chat Online

Simple Voice Online

Client-side addon for Simple Voice Chat:
when the Minecraft server has no voice chat installed, addon users on that
server can still talk to each other.

How it works

Voice goes peer-to-peer whenever possible:

SVC client ⇄ loopback bridge ⇄ P2P engine ══ direct UDP ══► other players
                                     ⇅ (fallback only)
                                    relay

• On joining a server, the mod waits ~5 s for a real SVC SecretPacket. If
  none arrives, it connects to the relay's WebSocket, joins a room keyed
  by the server address, and receives a shared room key plus the peer list.
• Peers exchange address candidates (local interfaces + relay-observed
  public address) and hole-punch a direct UDP path — the ICE approach with
  a compact custom protocol.
• Voice frames are Opus, sealed once per frame with the room key
  (AES-128-GCM) and sent directly to every punched peer. Pairs whose NATs
  defeat punching fall back to blind forwarding via the relay, which never
  touches crypto or audio.
• The local SVC client is pointed at an in-process loopback bridge, so all
  audio capture/playback is stock Simple Voice Chat.

If the server later turns out to have voice chat, SVC's real connection
replaces the fallback automatically.

Settings

In-game settings screen: press O (rebindable, "Simple Voice Online" key
category) or open it through ModMenu if
installed. The screen shows the live connection status (state, peers and
whether each one is direct or relayed) and offers a manual Reconnect
button. All changes apply immediately.