Real Time Updates hard
WebRTC is known for audio/video, but its 'Data Channels' allow sending arbitrary data. Which protocol does it use to provide reliability (retransmission) over UDP?
- A SCTP (Stream Control Transmission Protocol).
- B TCP.
- C QUIC.
- D Raw UDP.
Answer: A. SCTP (Stream Control Transmission Protocol).
WebRTC Data Channels wrap SCTP packets inside UDP/DTLS. SCTP provides configurable reliability—you can choose 'Reliable Ordered' (like TCP) or 'Unreliable Unordered' (like UDP) for the same channel.
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