SLS (SRT live server)

Dockerized version of Edward Wu's SRT Live Server (SLS) and Haivision's SRT SDK All credit should go to the original tool author(s) - this is just a dockerization for convenience and portability.

Requirements:

• Docker 24.x or later

To build, just execute the script build.sh.

To deploy in Akamai Connected Cloud, just execute the script deploy.sh.

Deployment settings:

You can customize your deployment by editing the file iac/settings.json. If the file doesn't exist, just create it using the content of the template iac/settings.json.template. You also will need to set up the credentials of the Akamai Connected Cloud in the file iac/.credentials. If the file doesn't exist, just create it using the content of the template iac/.credentials.template. Go to the Akamai Cloud Manager, create your API credential and then update the iac/.credentials file.

Streaming settings:

• Default listen port is 1935/UDP. Note that SRT doesn't technically have a default protocol port, so you will have to explicitly call this out in stream URLs (see below). 1935/TCP is what RTMP uses, so this makes it simpler to remember.
• Default latency is 200ms. (Nimble Streamer recommended no lower than 120ms no matter what, Haivision can do lower on hardware). If your streams are getting "confetti" you may want to set this higher, but I've found this to be a safe default in using OBS and Larix SRT streams over a reasonable internet connection. Think of this as a "safety buffer" for connection burps.
• There are two "endpoints", a publisher and an application.
• Publishing is for sending, application is for receiving/play.
• They are "stream/live" and "play/live", respectively. I changed them from the author's defaults to make them a bit less confusing.

If you want to customize the settings, just specify the following environment variables in the iac/docker-compose.yml:

• LATENCY (Default 200)
• THREADS (Default 2)
• CONNECTIONS (Default 300)
• BACKLOG (Default 100)
• IDLE_TIMEOUT (Default 60)
• LISTEN_PORT (Default 1935)

Example Sending of SRT in OBS:

• In the setup menu under "stream", select "Custom..." leave the Stream Key field blank.
• Put the following url: srt://<your.server.ip>:1935?streamid=stream/live/<yourstreamname>.

Example of Receiving of SRT in OBS:

• Add a Media Source.
• Put the following url to receive: srt://<your.server.ip>:1935?streamid=play/live/<yourstreamname>.

References:

• https://github.com/Edward-Wu/srt-live-server
• https://blog.wmspanel.com/2019/06/srt-latency-maxbw-efficient-usage.html
• https://www.haivision.com/blog/all/how-to-configure-srt-settings-video-encoder-optimal-performance/