Which transport protocol is typically used for streaming audio/video, and why?

• A. UDP – lower overhead, no guaranteed delivery, tolerates some loss
• B. SCTP
• C. ICMP
• D. TCP – reliable but overhead

Answer: (A)

For streaming audio and video, keeping latency low matters more than ensuring every packet arrives. UDP provides a lightweight, connectionless transport with minimal overhead and no retransmission delays. It doesn’t guarantee delivery, and packets can be lost or arrive out of order, but the application—and often the media protocol on top of it—handles this with buffering, error concealment, or forward error correction. That quick, steady flow keeps playback smooth, especially for live or real-time streams.

In contrast, TCP guarantees delivery of every byte by using acknowledgments and retransmissions, which introduces latency and jitter that can disrupt real-time playback. ICMP is a diagnostic protocol, not used to transport media. SCTP adds reliability and multi-streaming features, but it’s not as widely adopted for streaming media and typically incurs more overhead than UDP in this context. Therefore UDP is the typical choice for streaming audio/video due to its lower overhead and tolerance for some data loss.