SFU WebRTC: Selective Forwarding for enterprise video
Short answer
An SFU (Selective Forwarding Unit) is a WebRTC server that receives each participant’s stream and forwards it selectively to others without transcoding. It keeps low latency, limits client CPU load, and scales multi-party meetings—the standard model for professional video infrastructure.
How does an SFU session work?
- Signaling (HTTPS/WSS): room creation, SDP exchange;
- ICE / STUN / TURN: network path to the SFU;
- Publish: each participant sends audio/video/screen to the SFU;
- Selective forward: SFU routes relevant streams per receiver;
- Adaptation: simulcast/SVC adjusts quality to bandwidth.
SFU vs MCU vs P2P
| P2P | SFU | MCU | |
|---|---|---|---|
| Model | Direct client links | Selective relay | Mixed composite stream |
| Transcoding | No | No | Yes |
| Latency | Lowest (1:1) | Low | Often higher |
| Scale | ~2–3 participants | Dozens to hundreds+ | Variable, costly |
| Modern pro usage | Short 1:1 | Standard | Legacy / hardware rooms |
FAQ
When is an SFU required?
From 3+ participants in real-time interaction, P2P becomes unsustainable; SFU is the expected architecture.
Does SFU work on corporate networks?
Yes with documented STUN/TURN and firewall rules—part of enterprise rollout.
How does SFU relate to the video API?
The SFU is the media plane; video API and signaling are the control plane for your applications.
Key takeaways
- SFU is the distribution layer of professional WebRTC—not a replacement for WebRTC standards.
- Prefer SFU over MCU for scalable browser-based meetings.
- Size STUN/TURN and SFU capacity with your IT team before production rollout.
Next step
Request a quote to scope SFU capacity, TURN, and sovereign hosting.