--- title: "Coturn" date: 2022-03-29 short_desc: 'A STUN and TURN server that allows users to perform WebRTC calls while being behind NATs.' icon: "webrtc.svg" img: "webrtc.svg" tags: ['service'] --- [Coturn](https://github.com/coturn/coturn) is a libre **STUN** and **TURN** server software that allows users of chat protocols (Such as [XMPP](/prosody) and [Matrix](/matrix)) to perform WebRTC **voice and video calls** despite them being behind NATs. Almost every self-hosted voice and video conferencing program (such as [Jitsi](/jitsi) and [Nextcloud\'s](/nextcloud) Talk app) will **require** Coturn or some other equivalent turnserver to function properly. ## Installation Coturn is available in the Debian repositories: ```sh apt install coturn ``` ## Configuration ### Base configuration Coturn\'s configuration file is `/etc/turnserver.conf`. There are a few aspects that need to be changed in order to get a fully-functioning turnserver. Here is an example of some sane defaults: ```md server-name={{}}turn.example.org{{}} realm={{}}turn.example.org{{}} listening-ip=your_public_ip listening-port=3478 min-port=10000 max-port=20000 ## The "verbose" option is useful for debugging issues verbose ``` ### Authentication There are two options for authentication on a turnserver: 1. **Usernames** and **passwords,** 2. or **authentication secrets.** Depending on what self-hosted service is being used in conjunction with Coturn, you may need one or the other of these two options. #### Usernames and Passwords To utilize username and password authentication with Coturn, add the following configuration in `turnserver.conf`: ```txt lt-cred-mech user=username:password ``` #### Authentication Secrets To utilize authentication secrets with Coturn, add the following configuration in `turnserver.conf`: ```txt use-auth-secret static-auth-secret={{}}your_auth_secret{{}} ``` ## TURNS (TLS Encryption) Some self-hosted services (such as Matrix and XMPP) may support the use of **TURNS:** An encrypted version of TURN, which allows for WebRTC connections to be established with the use of an encrypted TLS tunnel, just like HTTPS allows for encrypted viewing of websites. To utilize TURNS, certificates need to be declared for **turn.example.org** in `turnserver.conf`: ```txt cert=/etc/letsencrypt/live/{{}}turn.example.org{{}}/fullchain.pem pkey=/etc/letsencrypt/live/{{}}turn.example.org{{}}/privkey.pem ``` ## Starting Coturn After all configuration changes are complete, Coturn can be started with its systemd daemon: ```sh systemctl restart coturn ``` Congratulations! You\'ve successfully setup a Coturn server! ------------------------------------------------------------------------ *Written by [Denshi.](https://denshi.org) Donate Monero at 48dnPpGgo8WernVJp5VhvhaX3u9e46NujdYA44u8zuMdETNC5jXiA9S7JoYMM6qRt1ZcKpt1J3RZ3JPuMyXetmbHH7Mnc9C [\[QR\]](https://denshi.org/images/xmr.png)*