Comparative Study of WebRTC Open Source SFUs for Video Conferencing

WebRTC capable media servers are ubiquitous, and among them, Selective Forwarding Units (SFU) seem to generate more and more interest, especially as a mandatory component of WebRTC 1.0 Simulcast. The two most represented use cases implemented using a WebRTC SFU are video conferencing and broadcasting. To date, there has not been any scientific comparative study of WebRTC SFUs. We propose here a new approach based on the KITE testing engine. We apply it to the comparative study of five main open-source WebRTC SFUs, used for video conferencing, under load. The results show that such approach is viable, and provide unexpected and refreshingly new insights on the scalability of those SFUs.