Fast Streaming | Introducing Microsoft Windows Server(TM) 2003

Fast Streaming refers to a set of features in Windows Media Services that significantly improves the quality of the streaming experience. Fast Streaming is based on the latest technologies and delivers compelling audio and video content over a variety of networks ”even when network connections are unreliable. Fast Streaming is possible because of the following four components :

Fast Start
Fast Cache
Fast Recovery
Fast Reconnect

Fast Start

Fast Start provides an instant-on playback experience with no buffering delay, whether playing a single piece of content or switching between on-demand clips or broadcast channels.

Before it can start playing content, Windows Media Player must buffer a certain amount of data. When streaming to clients who use Windows Media Player for Windows XP or a later version of the player, you can use Fast Start to provide data directly to the buffer at speeds higher than the bit rate of the content requested . This lets users start receiving content more quickly. After the initial buffer requirement is fulfilled, on-demand and broadcast content streams at the bit rate defined by the content stream.

Using Fast Start provides a better experience for users when playing back your content. Users can fast-forward and rewind content without additional delay and rebuffering. A player that connects through broadband networks starts playing the content more quickly, making the experience much more like viewing a television program or listening to a radio broadcast. Content delivered from your server by using server-side playlists switches smoothly and seamlessly between content items. Additionally, the buffering of data makes the player resistant to playback errors resulting from lost packets or other network issues.

Fast Cache

Fast Cache provides an always-on playback experience by streaming content to the Windows Media Player cache as fast as the network will allow, reducing the likelihood of an interruption in play as a result of network issues.

For example, using Fast Cache, the server can transmit a 128-kilobits-per-second (Kbps) stream at 700 Kbps. The stream is still rendered in Windows Media Player at the specified data rate, but the client is able to buffer a much larger portion of the content before rendering it. This allows the client to handle variable network conditions without a perceptible impact on the playback quality of either on-demand or broadcast content. This capability is useful in the following situations:

The available network bandwidth of the client exceeds the required bandwidth of the content ”for example, clients that use a cable modem, a DSL connection, or a corporate intranet.
The network connectivity is intermittent or has high latency ”for example, wireless networks.
The quality of the content received is of paramount importance ”for example, businesses that provide pay-per-view movies.

Fast Recovery

Fast Recovery works in conjunction with Forward Error Correction (FEC) to provide redundant packets of information to clients that are using wireless connections. Providing redundant packets ensures that no data is lost as a result of connectivity disruptions. Because of FEC, Windows Media Player can usually recover lost or damaged data packets without having to request that the data be re-sent by the Windows Media server.

In environments that are subject to latency problems, such as satellite networks and other wireless networks, this process of receiving data is much more efficient. And it's easy to specify the amount of error correction data transmitted per span of data sent using the Windows Media Services user interface.

Fast Reconnect

Fast Reconnect automatically restores live or on-demand player-to-server and server-to-server connections if disconnected during a broadcast. This ensures an uninterrupted viewing experience.

If the client was connected to an on-demand publishing point, the client restarts playback at the point at which the connection was lost by synchronizing itself with the content timeline. If the content includes video, the client estimates the approximate video frame at which the connection was lost. If the content is indexed, this estimate is more accurate. If the client is connected to a broadcast publishing point, the client reconnects to the broadcast in progress. Depending on the content, the user might experience a gap in the broadcast.

Fast Reconnect can be used with clients that connect through any of the default connection protocols: Microsoft Media Server (MMS), Hypertext Transfer Protocol (HTTP), and Real Time Streaming Protocol (RTSP). Fast Reconnect is available for both broadcast and on-demand streaming.

Top