Creating Cache Proxy Plug-ins

A Windows Media cache proxy server can stream content to clients from internal storage, or it can proxy content to clients from another server. When a client requests content, the cache proxy server must determine whether the content has been cached. If it has, but if the content has expired, the server must contact the origin server to determine whether the cached content is up to date. Expiration is specified by the content administrator to indicate the date past which content cannot be sent to a client. If the content is fresh, the cache proxy server can stream it from internal storage. If the content has not been cached or is stale, the cache proxy server can disconnect the client, redirect the client to an alternate URL or an alternate proxy server, proxy the content from the origin server, or perform some other action. The actions taken by the server are referred to as cache proxy policy. Windows Media Services uses a cache proxy plug-in to set policy. You can also use a cache proxy plug-in to administer a cache.

No cache proxy plug-in is provided with Windows Media Services. You must create your own as described in the following sections. How you choose to implement cache proxy policy is entirely up to you. The following sections highlight best practices when appropriate.

Section

Description

Cache Proxy Concepts

Defines common terms used when discussing cache proxy servers.

Standard Cache Proxy Topologies

Introduces typical cache proxy layouts.

Windows Media Server Cache Proxy Functionality

Discusses cache proxy functionality supported by the server. The functionality can be implemented by either the server or a cache proxy plug-in.

Implementing Cache Proxy Functionality

Identifies the interfaces needed to create a custom cache proxy plug-in and discusses how to create policies to handle basic proxy, expired content, unexpired content, and cache misses.

See Also

Concepts

Programming Guide