📝 System Design Interview Classics · C4 Architecture · Pro
Video Upload and Streaming (YouTube-style)
How uploaded videos become streamable: resumable upload, transcoding into several qualities, storage, and delivery through a CDN with adaptive bitrate.
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Drawing diagram…
What this diagram shows
- Uploads go straight to object storage with resumable chunks
- Each video is transcoded into several resolutions in parallel
- Viewers get adaptive streaming from the nearest CDN edge
Prompt used
Video platform design: creators upload through an upload service that issues resumable, pre-signed upload URLs to object storage. A new upload triggers a transcoding pipeline that splits the video and produces 240p to 1080p HLS renditions with thumbnails. Metadata is stored in a metadata service with MySQL. Viewers load a watch page, and the player streams HLS segments from a CDN that pulls from object storage.
Mermaid code
C4Container
title Video Upload and Streaming
Person(creator, "Creator", "Uploads videos")
Person(viewer, "Viewer", "Watches videos")
System_Boundary(vp, "Video Platform") {
Container(up, "Upload Service", "Go", "Pre-signed resumable uploads")
Container(tc, "Transcoding Pipeline", "FFmpeg workers", "HLS renditions and thumbnails")
Container(meta, "Metadata Service", "Java", "Titles, owners, status")
Container(watch, "Watch Service", "Node.js", "Watch pages and manifests")
ContainerDb(obj, "Object Storage", "S3", "Raw and encoded video")
ContainerDb(db, "Metadata DB", "MySQL", "Video records")
}
System_Ext(cdn, "CDN", "Edge caching")
Rel(creator, up, "Uploads", "HTTPS")
Rel(up, obj, "Writes raw file")
Rel(obj, tc, "Triggers on new file")
Rel(tc, obj, "Writes renditions")
Rel(tc, meta, "Marks ready")
Rel(meta, db, "Reads/writes")
Rel(viewer, watch, "Opens video")
Rel(watch, meta, "Gets details")
Rel(viewer, cdn, "Streams HLS segments")
Rel(cdn, obj, "Pulls on miss")Related templates
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