About reverse proxy
Applies To: Windows Server 2008, Windows Server 2008 R2
The WMS Cache Proxy plug-in in Windows Media Services 2008 allows the cache/proxy server to function as a reverse proxy server, which is a proxy server that is configured to be responsible for servicing all client requests. For a unicast broadcast, a reverse proxy server reduces the load on the origin server by streaming multiple unicast streams while receiving only one stream from the origin server. For on-demand content, a reverse proxy server reduces the load on the origin server by caching the content from the origin server and streaming it to clients from its cache.
To the client, the reverse proxy server appears to be the origin server. This enables you to isolate the origin server from clients. A reverse proxy server increases the security of your streaming media system because the client never connects to the origin server directly.
Authentication for reverse proxy servers differs from that of conventional cache/proxy servers. When the client submits a request for content and authentication is enabled, the content must first be authenticated by the reverse proxy server. After the client is authenticated, the reverse proxy server submits a content request to the origin server and must be authenticated by the origin server before it can begin proxying the content to the client.
To set authentication credentials for a reverse proxy server, do the following:
On the reverse proxy server, run the following script. In this script, password is the password and user_name is the user name you want to use to authenticate the origin server:
Dim server Set server = CreateObject("WMSserver.Server") Dim pp1 Set pp1 = server.PublishingPoints.Item("Cache/Proxy Broadcast") pp1.DistributionPassword = "password" pp1.DistributionUserName = "user_name"
On the origin server, configure the appropriate authentication plug-in to accept these values.
A large number of unicast streams can place an enormous burden on the origin server. You can increase the reliability of your streaming media system by caching and delivering content from multiple reverse proxy servers. If only one reverse proxy server is used, there is the potential for a single point of failure in that system. By using more than one reverse proxy server, you can reduce the chance that the system will fail due to a reverse proxy server fault.
For more information about implementing reverse proxy, see the Windows Media Services SDK.