Origin Server: An origin server is a user’s service server and the source of the accelerated data for delivery.
Retrieval Host: A retrieval host represents a host defined in the HTTP request header. It is the domain accessed by CDN nodes while retrieving the content from origin servers.
In case an origin server hosts several websites, then the retrieval host must define the domain from which content is retrieved. The origin server identifies the access address of the user’s retrieval request, i.e., the origin server’s IP address. The retrieval host will determine which site the retrieval request will visit.