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This section describes the practical application and deployment of Windows Media Services. Since Windows Media Services is an extremely versatile and configurable technology, you can use it to achieve a suitable streaming media solution for almost any situation. The following information can assist you during the deployment process and enable you to use your knowledge of local hardware and network conditions to set up a streaming media solution that suits your needs.
Any streaming media project has three main stages: project planning, assembling and managing the content, and coordinating content distribution. In addition to these three stages, there are many initial precautions and follow-up steps that you can take to improve the streaming media process.
A streaming media system based on Windows Media Technologies typically consists of a computer running an encoder, such as Windows Media Encoder, a server running Windows Media Services, and a number of client computers running a player, such as Windows Media Player. The encoder converts both live and prerecorded audio and video content to Windows Media Format. The Windows Media server distributes the content over a network or the Internet. The player then receives the content.
In the typical user scenario, the user clicks a link on a Web page to request content. The Web server then redirects the request to the Windows Media server and starts the player on the user's computer. At this point, the Web server no longer plays a role in the streaming media process, since the Windows Media server establishes a direct connection with the player and begins streaming the content directly to the user.
The Windows Media server can receive content from several different sources. Prerecorded content can be stored locally on the server or retrieved from a networked file server. Live events can be captured using a digital recording device and processed through an encoder before being sent to the Windows Media server for broadcast. Windows Media Services can also rebroadcast content streamed from a publishing point on a remote Windows Media server.
An effective streaming media deployment requires that you successfully manage three primary factors: the bandwidth available to your audience, the capabilities of your network or Internet connection, and the streaming requirements of your content.
The first, most important, factor is your audience. The amount of bandwidth your audience has available plays a key role in determining the type and quality of the content you provide. A large, high-definition video stream with stereo sound requires more bandwidth than is available for clients using a standard, dial-up modem connection. You should also know how large your audience will be. Even a small number of high-speed streams can affect the performance of the average commercial network or Internet gateway.
Evaluating your network capacity is the second factor. A computer network such as a local area network (LAN) can transfer a limited amount of data at a given time. Each individual connection to that network uses up a portion of its capacity. As the total amount of data being transferred approaches the network limit, individual data connections begin to slow down. When planning your streaming media deployment, make sure that your network capacity is well beyond the bandwidth requirements of your content.
Content is the most flexible and diverse factor. With both audio and video, improved content quality increases the bandwidth requirements. The use of quality improvement methods such as multiple-bit-rate encoding or variable-bit-rate encoding can create large differences in necessary bandwidth. Before it can be streamed to the audience, live and prerecorded content goes through the encoding process. The choices that are made during this process have a significant impact on the range of audience you can reach and the amount of necessary bandwidth.
This section covers the following topics: