Windows Media Services 2008 Overview

Applies To: Windows Server 2008, Windows Server 2008 R2

The Streaming Media Services role in the Windows Server 2008 operating system provides a platform for streaming digital media content to clients over networks.

The Streaming Media Services role in Windows Server 2008 includes the Windows Media Server role service, which is required to deploy your server computer as a Windows Media server. This role service includes Microsoft® Windows Media® Services 2008, which provides support for delivering digital media content to clients across a network.

The Streaming Media Services role also includes the following optional role services for managing a Windows Media server:

  • Web-based Administration. Provides support for remote Web-based administration of a Windows Media server.

  • Logging Agent. Provides support for logging statistics from clients that receive multicast broadcast or advertising content from a Windows Media server.

What is a Windows Media server?

A Windows Media server streams digital audio and video content to clients over the Internet or an intranet. These clients can be other computers or devices that play back the content using a player, such as Windows Media Player, or they can be other computers that are running Windows Media Services (called Windows Media servers) that proxy, cache, or redistribute the content. Clients can also be custom applications that have been developed by using the Windows Media SDK components.

The content that your Windows Media server streams to clients can be a live stream or a prerecorded digital media file. For live content, the server connects to encoding software, such as Microsoft® Expression® Encoder, that can broadcast a live stream in a format supported by the server.

The following types of organizations find Windows Media Services to be especially useful:

  • Hosting companies that deliver a fast-streaming experience to viewers in homes and offices.

  • Enterprises that manage network resources while delivering rich communications for executive broadcasts, online learning, marketing, and sales.

  • Wireless companies that deliver wireless broadband entertainment services by using scalable and reliable Windows Media servers.

  • Internet broadcasters that deliver content for radio, television, cable, or satellite.

  • Film and music distributors that distribute audio and video content in a secure manner without excessive buffering or network congestion.

  • IPTV professionals that deliver a high-quality IPTV experience on local area networks (LANs).

Features in Windows Media Services

The following features and functions in Windows Media Services 2008 make it ideal for delivering high-quality live and on-demand streaming experiences:


The features in Windows Media Services differ, depending on which version or edition of the Windows Server operating system that you are running. For more information, see Decide which version of Windows Server is right for you.

  • Cache/Proxy Management. You can configure a Windows Media server either as a cache/proxy server or as a reverse proxy server so that it can provide caching and proxy support to other Windows Media servers. A Windows Media server that can cache and proxy your digital media content reduces operating costs and provides a better viewing experience for users by conserving network bandwidth, decreasing network-imposed latency, and offsetting the load on the origin server.

  • Advanced Fast Start. Fast Start delivers an instant-on playback experience by eliminating buffering time. When a viewer connects to a stream, the first few seconds of data is sent using the maximum available bandwidth so that playback can begin as soon as possible. Advanced Fast Start adds to these capabilities by enabling Windows Media Player to begin playing content as soon as its buffer receives a minimum amount of data, further reducing the time a user must wait to begin receiving the stream.

  • Play While Archiving. Broadcast content can be archived to a file, and the archived content can be made available for on-demand requests or rebroadcast, even before the broadcast is finished being archived.

  • Advanced FF/RW. Enhanced fast-forward and rewind ("trick mode") functionality for the video part of the content stabilizes network bandwidth availability by using separate files for each FF/RW speed. This creates a fixed bandwidth requirement per client, regardless of playback speed, and greatly smoothes the FF/RW experience. Potential server performance bottlenecks are reduced because the server must read less presentation data from the source content disk, while delivering a seamless experience to clients.

  • Broadcast AutoStart. In the event of an interruption, such as a power failure, broadcast publishing points can be configured to begin running again automatically whenever the Windows Media server starts, so that viewers experience less disruption when they view streaming content.

  • Absolute Playlist Time. Absolute Playlist Time adds the playlist timing value wallclock. You can use the wallclock value to automate broadcast schedules by assigning real-world clock values in Coordinated Universal Time (UTC) to attributes in server-side playlists.

  • Encoder Failover URL Modifiers. If your primary encoder fails or is stopped, you can configure Windows Media Services to pull content from an alternative encoder or other content source after a specified period of time by using URL modifiers in the path of the primary encoder. If you use redundant encoders or other alternative content sources, you increase the reliability of the source content.

Installing Windows Media Services

The Streaming Media Services role and role administration tools for the Remote Server Administration Tools feature in Server Manager are not included in Windows Server 2008. You must run a Streaming Media Services role installer file on the updated platform. You can install Streaming Media Services role installer files on the full installation option for Windows Server 2008 or on the Server Core installation option. The full installation option includes the entire Windows Media Services user interface, whereas the Server Core installation option installs a minimal installation of Windows Media Services. Windows Media Services on the Server Core installation option is managed from the Command Prompt window, reducing management requirements and attack surface. For more information about Streaming Media Services installation, see the Release Notes for Windows Media Services 2008.

If you are upgrading the operating system to Windows Server 2008, you can move your existing Windows Media server configuration settings and digital media content. For more information, see the Windows Media Services 2008 Upgrade and Migration Guide.

You can estimate the hardware requirements for a Windows Media server network, based on your estimated audience size and the bandwidth consumed by the digital media content that you want to deliver. For more information about common performance issues, limitations, and performance monitoring techniques, see Optimizing Windows Media Services.

Managing a Windows Media server

Windows Media Services includes the following management interfaces:

  • On the full installation option for Windows Server 2008, you can use the Windows Media Services snap-in for Microsoft Management Console (MMC) to manage the local Windows Media server. To open the snap-in, click Start, click All Programs, click Administrative Tools, and then click Windows Media Services.

  • You can install the optional Web-based Administration role service on the local Windows Media server and then manage the server by opening the Windows Media Administration site (http://server_name:8080/default.asp) in a Web browser on a remote computer. For more information, see Administering Windows Media servers remotely.

  • You can install Remote Server Administration Tools for Windows Media Services on a computer that runs Windows Vista® or Windows® 7 and then manage your remote Windows Media server from the client computer. To start the Windows Media Services snap-in for MMC on the client computer, click Start, click Run, and then type wmsadmin.

For more information

  • To learn more about the Streaming Media Services role, you can view the Help on your server. To do this, open Windows Media Services snap-in as described in the previous section and press F1.

  • For additional information about the Streaming Media Services role and Windows Media technologies, see the Windows Media Home page. This Web site is your window to all the Windows Media technologies and links to related information, including an extensive collection of books, articles, videos, and technical documents that showcase Windows Media tools and technologies.