Simulcast is a technique by which a WebRTC client encodes the same video stream twice in different resolutions and bitrates and sending these to a router who then decides who receives which of the streams. Simulcast adds more flexibility to how media servers can operate at scale.

Simulcast is closely related to SVC, where a single encoded video stream can be layered and each participant receives only the layers that he can process.

About WebRTC Glossary

The WebRTC Glossary is an ongoing project where users can learn more about WebRTC related terms. It is maintained by Tsahi Levent-Levi of

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