Media Streaming
High Priority37 min readUpdated June 17, 2026
AI Mock Interview
Practice this topic in a realistic system design interview
Media streaming is one of the most demanding workloads in distributed systems. It combines large data volumes, timing-sensitive playback, expensive media processing, and highly variable client networks.
Get any of these wrong, and your viewers see buffering, stuttering, or pixelated video.
The first interview move is to clarify the product: VOD, live broadcast, or low-latency interactive media. That choice drives the protocol, latency target, storage strategy, CDN behavior, and cost profile.
Interview Answer Shape
In an interview, avoid starting with codecs or FFmpeg commands. Start with the product mode:
- Clarify whether the system is VOD, live broadcast, or interactive real-time media.
- Pick the viewer protocol from the latency and scale target: HLS/DASH for scale, LL-HLS for lower-latency broadcasts, WebRTC for sub-second interaction.
- Describe the core pipeline: ingest, transcode/package, store segments, serve from origin/CDN, adapt in the player.
- Call out the main tradeoffs: latency vs cacheability, quality vs bandwidth, codec efficiency vs compute/device support, and cost vs redundancy.
- Add operational concerns only after the main architecture: monitoring QoE, backpressure in processing, multi-CDN, and fallback behavior.