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Describes Microsoft Windows Media technologies that can be used to set up a server system that delivers broadcast music and video to a personal computer or mobile device. Outlines some basic information about how to implement the server technology used in this type of scenario.
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Janet Thomas Microsoft Corporation January 2006
Applies to: Microsoft® Windows Server™ 2003 operating systems with Microsoft Windows Media® Services Microsoft Windows Media Encoder Microsoft Windows Media Encoder 9 Series Software Development Kit (SDK)
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IntroductionMicrosoft® Windows Media® technologies enable you to broadcast live and prerecorded video, such as a television show, from a server, over a network, to a personal computer or a mobile device. The same technologies can be used to broadcast live or prerecorded audio, such as a radio station. To enable a broadcast scenario, the video and audio are compressed using Windows Media Encoder, and then accessed through a Web page that contains a reference to the source of the digital media content. When using Windows Media technologies, the source is a server running Windows Media Services.
For broadcasting, an alternate Radio Frequency (RF) spectrum, other than what is used for a cell phone signal, is usually implemented. Multicasting is also usually implemented. Multicasting is a method of transmitting a single stream to a large audience simultaneously. This gives you the ability to literally put a broadcast transmitter up on a cell tower and broadcast content to millions of people through that single transmitter. The network you will use to deliver the broadcast must be capable of handling multicast.
Several digital mobile broadcast technologies that are designed specifically for mobile broadcasting are available, such as Digital Video Broadcasting: Handheld (DVB-H), Digital Multimedia Broadcasting (DMB), Terrestrial Integrated Services Digital Broadcasting (ISDB-T), and Digital Audio Broadcasting (DAB). The content can also be streamed to mobile device over a traditional wireless data network.
When using Windows Media Services, customers that receive a broadcast cannot control the start of the content or the rate of playback, and they cannot fast-forward or rewind the stream. The server is in control of the stream.
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TechnologiesMicrosoft® Windows Media® Encoder enables you to convert audio and video files to Windows Media format, or to compresses a live audio or video feed in real time before it is passed to the server running Windows Media Services.
Radio and television shows can be live or prerecorded files. When you are working with prerecorded files, such as a playlist used for Internet radio or a prerecorded television show, you can use the Windows Media Encoder to convert the files to the Windows Media file format.
With Windows Media Services, which runs on Windows-based servers, you can unicast and multicast live or stored media. When your customer chooses to play a broadcast, the Windows Media Server broadcasts the content to the media player on the personal computer or the mobile device. For more information about unicast and multicast, see Serving for Windows Media Services: The Basics.
The following tables describe the Windows Media technologies that can be used to broadcast live or prerecorded audio and video over a network.
| Technology | Description |
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Streaming server and a Web server
| Microsoft Windows Server™ 2003 operating systems with Internet Information Services (IIS) and with Windows Media Services enabled are ideal for streaming audio. Windows Media Services are designed specifically for the task of delivering live or on-demand streaming media. The Web server is used to host the Web site that gives your customers access to the content over the Internet.
Microsoft partners can set up this type of system for you or provide you with a Windows Media hosting service.
| Windows Media Encoder and Software Development Kit (SDK)
| The encoder compresses and encodes audio and video content to a Windows Media file or live stream. The SDK enables you to automate the encoding process for large numbers of media files.
To download the Windows Media Encoder 9 Series SDK, see Windows Media Encoder 9 Series SDK on the Microsoft Download Center.
Several Microsoft partners have already implemented this technology and are available to assist you with your encoding needs. For more information, search the Windows Media Serivce Provider Program Directory.
| Media Streaming protocols
| The Media Streaming protocols are used to negotiate connections between Windows Media servers, encoders, content sources and the personal computer or mobile device requesting the stream.
The protocols used to stream Windows Media-based content are:Real Time Streaming Protocol (RTSP) Microsoft Media Server (MMS) protocol Hypertext Transfer Protocol (HTTP) Multicast streaming
For more information about licensing these protocols, see the Media Streaming Server Task Protocol Details.
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ImplementationIf you are like most mobile service providers, you are more likely to take advantage of content provider's services than to create your own content for broadcast. For example, you could work with an existing radio station or a news organization to capture and broadcast live news feeds, or you could work with a media production organization that processes high volumes of television shows, or movies. In either case, Windows Media Encoder can be used to compress both live and prerecorded audio and video into a Windows Media file format that is suitable for broadcast.
Multicasting your broadcast is a good choice if bandwidth is an issue because one stream can feed a virtually limitless number of clients. With multicast broadcast, the server does not create a connection to any client. Instead, the server delivers the content to a Class D Internet Protocol (IP) address on the network, and any client on the network can receive it. This conserves network bandwidth. During a broadcast, the client receives the stream, but does not control the stream. For example, in most cases, the user cannot pause, fast-forward, or rewind the stream.
The broadcasts may be delivered using digital mobile broadcast technologies that can provide more reliability and lower power demand, such as Digital Video Broadcasting: Handheld (DVB-H), Digital Multimedia Broadcasting (DMB), Terrestrial Integrated Services Digital Broadcasting (ISDB-T), and Digital Audio Broadcasting (DAB). The content can also be streamed to mobile devices over a traditional wireless data network.
Microsoft has a large network of partners that are already using Windows Media technologies and can assist you with your broadcasting needs. For more information on a Microsoft Windows Media Service Provider in your area, search the Windows Media Service Provider Program Directory.
Windows Media EncoderWhen you are working with live audio or video Windows Media Encoder converts the program signal into a live Windows Media-based stream. When you are working with prerecorded audio or video, Windows Media Encoder converts the files to Windows Media Audio (WMA) or Windows Media Video (WMV) files that are the appropriate size and bit rate for broadcasting.
Broadcast content often contain digital media that needs to be protected from unauthorized viewing or copying. Secure content distribution is possible through the Windows Media Encoder. In a live event, the content that is captured is protected on the fly. This also works for broadcasts of pre-encoded content. If you are doing a real-time broadcast of a file, the encoder can apply Windows Media digital rights management technology during the broadcast. Windows Media Encoder also includes complete integrated support for third-party license server providers, allowing content owners to easily define rights and distributed uses for their content.
To download the Windows Media Encoder, go to the Microsoft Download Center and search for Windows Media Encoder 9 Series.
Windows Media Encoder Software Development KitThe Windows Media Encoder 9 Series Software Development Kit (SDK) is designed for anyone who wants to develop a Windows Media Encoder application by using a powerful automation-based application programming interface (API). With this SDK, a developer using C++, Microsoft Visual Basic®, or a scripting language can capture multimedia content and encode it into a Windows Media-based file or stream. These tools are great for automating the encoding process for custom applications and solutions that allow you to encode large volumes in a short amount of time.
To download the Windows Media Encoder 9 Series SDK, go to the Microsoft Download Center and search for Windows Media Encoder 9 Series SDK.
Windows Media ServicesWindows Media Services handles the special requirements of broadcasting Windows Media content on the Internet. Windows Media Services provides features, such as lower cost, unmatched audio and video quality at any bit rate, dynamic content programming and advertising support, Live DRM (which prevents unauthorized viewing), and other features.
For more information about these features, see Windows Media and Web Distribution for Broadcasters.
You can set the broadcast up yourself, or you can work with a Microsoft Certified Hosting Provider to assist you. Hosting providers can help you set up a broadcast using the advanced features of Microsoft Windows Media 9 Series. The program consists of two designations: Premier Certified Hosting Providers and Certified Hosting Providers.
The Premier Certified Hosting Provider Program rates providers on their ability to provide consistent, high-quality streaming experiences. Testing is conducted on live, real-world streams, and hosting providers must undergo continuous testing to remain certified. Windows Media 9 Series Premier Certified Hosting Providers have demonstrated exceptional reliability and serving capacity beyond the basic requirements of the Certified Hosting Providers program. For more information about contacting one of these providers, see Premier Certified Hosting Providers.
Windows Media 9 Series Certified Hosting Providers have demonstrated expertise using Windows Media 9 Series in successful hosting scenarios. Core capabilities include, but are not limited to, support for live and on-demand streaming and downloads, server-side playlists and advertising, Windows Media DRM for live and on-demand, bit rates up to 750 kilobits per second (Kbps) or greater, aggregate throughput of 8 gigabits per second (Gbps), and Microsoft Producer for Microsoft Office PowerPoint 2003. For more information about contacting one of these providers, see Certified Hosting Providers.
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For More InformationFor more information about dynamic advertising, see Advertising .
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