_rtsp-simple-server_ is a simple, ready-to-use and zero-dependency RTSP server and RTSP proxy, a software that allows multiple users to publish and read live video and audio streams over time. RTSP, RTP and RTCP are standardized protocol that describe how to perform these operations with the help of a server, that is contacted by both readers and publishers in order to negotiate a streaming protocol. The server is then responsible of relaying the publisher streams to the readers.
The `--network=host` argument is mandatory since Docker can change the source port of UDP packets for routing reasons, and this makes RTSP routing impossible. To avoid the option, disable UDP and expose the RTSP port, by creating a file named `rtsp-simple-server.yml` with the following content:
To change the configuration, it's enough to edit the `rtsp-simple-server.yml` file, provided with the executable. The default configuration is [available here](rtsp-simple-server.yml).
An RTSP proxy is usually deployed in one of these scenarios:
* when there are multiple users that are receiving a stream and the bandwidth is limited, so the proxy is used to receive the stream once. Users can then connect to the proxy instead of the original source.
* when there's a NAT / firewall between a stream and the users, in this case the proxy is installed in the NAT and makes the stream available to the outside world.
Users can then connect to `rtsp://localhost:8554/proxied`, instead of connecting to the original url. The server supports any number of source streams, it's enough to add additional entries to the `paths` section.
The last command works only on Linux; for Windows and Mac equivalents, read the [ffmpeg wiki](https://trac.ffmpeg.org/wiki/Capture/Webcam).
#### Remuxing, re-encoding, compression
_rtsp-simple-server_ is an RTSP server: it publishes existing streams and does not touch them. It is not a media server, that is a far more complex and heavy software that can receive existing streams, re-encode them and publish them.
To change the format, codec or compression of a stream, you can use _FFmpeg_ or _Gstreamer_ together with _rtsp-simple-server_, obtaining the same features of a media server. For instance, to re-encode an existing stream, that is available in the `/original` path, and publish the resulting stream in the `/compressed` path, edit `rtsp-simple-server.yml` and replace everything inside section `paths` with the following content:
WARNING: RTSP is a plain protocol, and the credentials can be intercepted and read by malicious users (even if hashed, since the only supported hash method is md5, which is broken). If you need a secure channel, use RTSP inside a VPN.