Microsoft's Live Smooth Streaming
Microsoft's Smooth Streaming extends Internet Information Services (IIS) 7.0 Media Services to provide adaptive streaming of media to Silverlight clients via HTTP.
Live Smooth Streaming is based on a scalable delivery method that makes full use of HTTP caches and segments.
Live Smooth Streaming brings PVR-style access and navigation to live video streams. Viewers can now join events in progress, quickly locate the beginning to catch up, rewind, pause, resume and return to the live broadcast.
The advantage of using HTTP-based delivery is that the existing HTTP infrastructure greatly increases live event availability. With HTTP, CDNs and content providers can take advantage of all the resources of their network without overrunning network capacity and disconnecting users from live events.
HTTP is a well established "open standard" protocol adopted by Internet users to deliver web pages and content.