Persisting Cached Content

Persisting Cached Content

It is recommended that the content stored on a cache server exactly reflect the content stored on the origin server. Therefore, the cache server must remove any content that has been removed from the origin server, and must refresh any content that has been updated on the origin server. A cache proxy plug-in can call the CompareContentInformation method on the IWMSCacheProxyServer interface to instruct the cache manager to determine the status of content cached on an origin server. If the content is not available because it has been removed from the origin server, it must also be removed from the cache server.

• Note   Typically, a cache proxy plug-in calls CompareContentInformation only if the content stored on the cache server has expired. The administrator of the content stored on an origin server can use the Windows Media Services user interface (UI) to specify when content expires. If the administrator specifies that the content never expires, by setting a property on the publishing point that instructs the cache manager to call the SetExpirationTime method on the IWMSDataContainerVersion interface with a value of -1, the plug-in does not typically call CompareContentInformation. Therefore, the cache server does not connect to the origin server to verify whether the content is up to date, and the content will remain on the cache server even though it may have been removed from the origin server.

See Also (General)

• Windows Media Server Cache Proxy Functionality

See Also (Visual Basic .NET)

• IWMSCacheProxyServer Object (Visual Basic .NET)
• IWMSDataContainerVersion Object (Visual Basic .NET)

See Also (C#)

• IWMSCacheProxyServer Object (C#)
• IWMSDataContainerVersion Object (C#)

See Also (C++)

• IWMSCacheProxyServer Interface
• IWMSDataContainerVersion Interface