Microsoft has released IIS Media Services 4.0, an integrated HTTP-based media delivery platform

IIS Media Services 4.0 is a set of media-related extensions for Microsoft Internet Information Services (IIS) 7 and higher. IIS Media Services provides an integrated HTTP-based media delivery platform, and includes:
Smooth Streaming. Enables adaptive streaming of on-demand media files for Smooth Streaming-compatible clients, including Microsoft Silverlight.
Live Smooth Streaming. Enables adaptive streaming of live media broadcasts for Smooth Streaming-compatible clients. A new Live Smooth Streaming feature in IIS Media Services 4.0 Beta 1 enables delivery of live media broadcasts to Apple mobile digital devices.
Transform Manager. Enables conversion of on-demand media files to Smooth Streaming presentations for Smooth Streaming-compatible clients and enables conversion of Smooth Streaming presentations to MPEG-2 TS segments that can be played by Apple devices.
Advanced Logging. Provides rich, real-time client- and server-side logging.
Bit Rate Throttling. Meters the speed at which media is delivered to a player.
Web Playlists. Enables secure sequencing and server-side control of media content.

You can also download two additional IIS extensions related to IIS Media Services 4.0:
Advanced Loggingg, with real-time client- and server-side logging
Application Request Routing (ARR), providing HTTP proxying and caching
Transform Manager, runs encoding tasks to convert media files to on-demand Smooth Streams for Silverlight clients and Apple mobile digital devices.

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