Optimize large file delivery

About the option

If you are serving content larger than 10 MB, we recommend using the Large Files Delivery Optimization. With this option, the CDN will make range requests to the origin to retrieve 10-MB chunks of the content. These chunks are then collected in the cache, and once the CDN has the necessary portions of the requested content, the response is assembled and returned to the end user.

A range request includes the Range HTTP header to indicate the byte or part of the content to be returned. For example, if the request has a Range: bytes=123537047-123545047 header, the CDN will request a 10-MB chunk from the origin (byte range 115343360-125829119), cache this chunk, and serve the requested range (123537047-123545047) to the end user.

For this option to work, the origin server must support range requests.

Configuration guidelines

Make sure to review these requirements and recommendations before configuring the option.

• The origin server must support HTTP Range Requests.
• The Content-Length and Etag headers must be consistent across the origin.
• This optimization will be applied to all contents in the CDN resource, which could lead to an increased load on the origin. Therefore, consider activating Origin Shielding before using this feature, or make any updates during off-peak hours.
• This option can be configured in the Resource Settings and Rules.
• Remember to purge the resource cache after updating this option.
• This option is mutually exclusive and cannot be used in conjunction with Fetch Compressed, Gzip Compression, and Brotli Compression within the Resource Settings or within the same rule.

Configuration steps

To configure Large Files Delivery Optimization option via the Control panel:

1. Go to CDN and select the CDN resource you want to configure.

2. In the navigation panel, under the Content section, click Large files delivery optimization.

3. Turn on the toggle for Enable Large files delivery optimization to enable the option.