I don't think there is comprehensive information about that. We all do pretty much the same, implement the Selective Forwarding Unit (SFU) model.
The idea is the SFU will receive a number of streams for each user (usually up to 3, in low, mid and high resolutions) and then it will forward one of them to each other participant depending on things like available bandwidth, requested video size, etc.
There are a number of Open Source implementations available, in case you want to study it deeper:
The idea is the SFU will receive a number of streams for each user (usually up to 3, in low, mid and high resolutions) and then it will forward one of them to each other participant depending on things like available bandwidth, requested video size, etc.
There are a number of Open Source implementations available, in case you want to study it deeper:
- Jitsi videobridge: https://github.com/jitsi/jitsi-videobridge
- Janus: https://github.com/meetecho/janus-gateway
- mediasoup: https://github.com/versatica/mediasoup
- (p)ion: https://github.com/pion/ion-sfu
- meddoze: https://github.com/medooze/media-server-node
And probably more!