svc-router

A UDP router for the Simple Voice Chat mod that pairs with mc-router to direct audio traffic to the correct backend server.

Overview

mc-router is a lightweight connection multiplexer that routes TCP traffic based on the server address (hostname) in the initial Minecraft handshake. This allows hosting multiple servers on a single public IP.

svc-router works alongside mc-router to handle the UDP traffic required by the Simple Voice Chat mod. It listens for connection webhooks to dynamically map a player's UDP voice packets to the correct backend server, ensuring voice chat works transparently across your backend.

Architecture

1. TCP Handshake: Player connects to mc-router.
2. Webhook Trigger: mc-router sends a POST webhook to svc-router containing the player's UUID and the target backend address.
3. Route Creation: svc-router creates an internal mapping: UUID -> Backend UDP IP.
4. UDP Voice Stream: The player's voice client sends UDP packets to svc-router. The router inspects the packet header for the UUID and forwards it to the mapped backend.

Configuration

1. Configure mc-router

You must configure mc-router to broadcast connection events to this application.

Add the -webhook-url flag to your startup command, pointing to the HTTP address of svc-router:

# Example: svc-router running on the same host, port 80
./mc-router -webhook-url "http://localhost:8080/event" ...

2. Running svc-router

Default Ports:

• UDP Listening: 0.0.0.0:24454 (Simple Voice Chat Traffic)
• HTTP Listening: 0.0.0.0:8080 (Webhooks)

Run via Docker (Example):

docker run -d \
  -p 24454:24454/udp \
  -p 8080:8080 \
  --name svc-router \
  jschuler99/svc-router:latest

Contributing

This project has undergone limited testing in live environments. Feedback and contributions are highly encouraged!

If you encounter any issues or have suggestions for improvements, please feel free to open an issue or submit a Pull Request.

Special Thanks

• itzg - For creating mc-router and providing the inspiration and webhook architecture that made this project possible.