# Coturn

This folder contains the role to deploy and manage a [Coturn](https://github.com/coturn/coturn) service.

## Description

[Coturn](https://github.com/coturn/coturn) is a free and open-source **TURN (Traversal Using Relays around NAT)** and **STUN (Session Traversal Utilities for NAT)** server.  
It enables real-time communication (RTC) applications such as **WebRTC** to work reliably across NATs and firewalls.

Without TURN/STUN, video calls, conferencing, and peer-to-peer connections often fail due to NAT traversal issues.  
Coturn solves this by acting as a **relay server** and/or **discovery service** for public IP addresses.

More background:  
* Wikipedia: [Traversal Using Relays around NAT](https://en.wikipedia.org/wiki/Traversal_Using_Relays_around_NAT)  
* Wikipedia: [Session Traversal Utilities for NAT](https://en.wikipedia.org/wiki/STUN)  
* Official Coturn Docs: [https://github.com/coturn/coturn/wiki](https://github.com/coturn/coturn/wiki)

## Overview

This role deploys Coturn via Docker Compose using the `sys-stk-semi-stateless` stack.  
It automatically configures:
- TURN and STUN listening ports
- Relay port ranges
- TLS certificates (via Let’s Encrypt integration)
- Long-term credentials and/or REST API secrets

Typical use cases:
- Nextcloud Talk
- Jitsi
- BigBlueButton
- Any WebRTC-based application

## Features

* Stateless container deployment (no database or persistent volume required)  
* Automatic TLS handling via `sys-stk-front-base`  
* TURN and STUN support over TCP and UDP  
* Configurable relay port ranges for scaling  
* Integration into Infinito.Nexus inventory/variable system

## Further Resources

* Coturn Project — [https://github.com/coturn/coturn](https://github.com/coturn/coturn)  
* Coturn Wiki — [https://github.com/coturn/coturn/wiki](https://github.com/coturn/coturn/wiki)  
* TURN on Wikipedia — [https://en.wikipedia.org/wiki/Traversal_Using_Relays_around_NAT](https://en.wikipedia.org/wiki/Traversal_Using_Relays_around_NAT)  
* STUN on Wikipedia — [https://en.wikipedia.org/wiki/STUN](https://en.wikipedia.org/wiki/STUN)