System design interview question
Design a Video Conferencing System
A video conferencing system carries real-time audio, video, and screen sharing between many participants with sub-300 ms glass-to-glass latency. Unlike streaming systems, it cannot buffer — every additional 100 ms of latency degrades conversational flow. The design relies on WebRTC for browser-native peer connections, an SFU (Selective Forwarding Unit) to scale from 2-person calls to 100-person meetings without burning bandwidth at clients, TURN/STUN servers for NAT traversal, and a media pipeline for recording, transcription, and live streaming.
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