What is Push CDN?
A push CDN requires content to be uploaded from the origin server or a storage bucket to CDN edge nodes in advance, rather than being pulled on demand.
A push CDN is a content delivery architecture in which the content provider proactively uploads (pushes) content from the origin server or storage system directly to the CDN edge servers before a user request arrives. Unlike a pull CDN, which fetches content on the first user request and then caches it, a push CDN pre-populates every edge node with the full payload. This is typically done via an API, a CLI tool, or direct FTP/SSH file transfer. Once uploaded, the content resides at the edge indefinitely until the provider manually removes or updates it.
How it works: The provider configures a distribution or a container on the CDN platform, then uploads assets (video files, software installers, large image sets, or any static binary) to the CDN's storage layer. The CDN replicates those files to points of presence around the world. When a user requests the file, the nearest edge server serves it immediately without any back-to-origin latency. File control (versioning, deletion, TTL expiration) is entirely manual or scheduled by the provider.
Where it sits in the stack: Push CDN is a complementary deployment model to pull CDN. It is especially suited for content that does not change often, is extremely large, or must be available with zero cold-start delay. Many commercial CDNs (e.g., Akamai, Fastly, Cloudflare R2/Stream, Bunny CDN) offer both pull and push modes. Push CDN is common for video-on-demand libraries, game patches, mobile app binary distributions, and software repositories. The trade-off is that storage costs are higher than pull caching, but origin load is eliminated and performance is maximized.
Key facts
- Content is uploaded to edge nodes before any user request arrives.
- No cold-start latency because content does not need to be fetched from origin on first hit.
- Provider must manually manage updates, deletions, and versioning at the edge.
- Ideal for large static assets (video, ISOs, APKs, firmware) that change infrequently.
- Storage costs at the edge are higher, but origin bandwidth is zero after the initial push.
How it works in practice
Related terms
References
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