HTTP Pull Zone
An HTTP Pull zone is used to pull content (e.g., website assets, live streams, or VoD files) from your origin server and cache it on CDN edge servers for faster delivery. The content is served as-is, which means no repackaging occurs. Its main uses include:
- Website Acceleration: It is commonly used for delivering static assets like CSS, JavaScript files, and images from your origin server to speed up website performance.
- Live Streaming: It can be used for delivering live streams (e.g., HLS/DASH) from the origin server to users via CDN. The content is fetched in real time and distributed to viewers.
- VoD Streaming: It can also serve Video on Demand (VoD) content, like HLS/DASH files, from the origin server. The CDN fetches the pre-packaged HLS/DASH files from your origin server and distributes them to end users.
VOD Pull Zone
A VOD Pull zone is specifically designed for on-demand video streaming, with a key difference from HTTP Pull zones in how it handles video formats. Its main use is:
- MP4 to HLS Conversion: A VOD pull zone pulls MP4 files from your origin server and converts them into HLS (HTTP Live Streaming) format on-the-fly. This allows the CDN to repackage the content into smaller HLS chunks for smooth, adaptive streaming. This process is done dynamically, so the original MP4 file doesn’t need to be stored in HLS format on the origin server.
In summary, while both HTTP Pull and VOD Pull zones serve VoD content, the VOD Pull zone is optimized for pulling MP4 files and converting them to HLS for better video streaming performance across CDN edge servers, whereas HTTP Pull zones deliver content in its original format.