When Dynamic Route for CDN (DCDN) receives a request from a client and cannot return the requested resource from the cache of the node nearest to the client, it retrieves the requested resource from the origin. Then, it returns the retrieved resource to the client and also caches the resource to the node. You can configure back-to-origin features based on your needs to improve resource access efficiency.

DCDN supports the following back-to-origin features.
Feature Description
Configure the origin host You can specify the domain type of the origin host for DCDN nodes to retrieve resources from the origin.
Configure the static origin protocol policy You can specify the origin protocol policy to be used by DCDN when it communicates with the origin.
Enable authorization to access private buckets You can enable the access permission on private Object Storage Service (OSS) buckets when OSS buckets are used as origins. This helps to prevent resource hotlinking.
Disable authorization from accessing private buckets You can revoke the permissions of the corresponding role in the Resource Access Management (RAM) console to disable the private bucket access permission.
Configure an origin SNI If your origin IP address is bound to multiple domains, you must set a Server Name Indication (SNI) value to ensure that the DCDN node can access the origin server over HTTPS.
Configure object chunking You can enable the object chunking feature, so that DCDN can retrieve content from the origin based on HTTP range requests. This helps to reduce the back-to-origin data usage and shorten the resource response time.
Customize an HTTP header You can add or remove HTTP headers if you configure DCDN to communicate with the origin over HTTP.