Differentiating Local Requests from Cache Proxy Requests
When a client connects to a Windows Media server, the server examines the URL to determine whether the requested content is located locally or remotely. If the content is stored on another computer, the server sends the client request to the cache manager, and the cache manager interacts with the cache proxy plug-in to determine how to process the request. The server only considers the host portion of the URL when attempting to determine whether the request is local. Therefore, URLs that specify the local computer are processed locally even if the requested content does not exist on the local computer.
Your cache proxy plug-in can use the WMS_EVENT_LOGICAL_URL_TRANSFORM member of the WMS_EVENT structure to modify the requested URL before the server checks it. You can map requests for content on another server to local content, and the reverse is also true. If the client requests local content, the server sends the WMS_EVENT_PHYSICAL_URL_TRANSFORM event notice.
Note
When the Windows Media server is configured as a reverse proxy server, the client request is always sent to the cache manager. For more information, see Implementing Reverse Proxy.