How do you choose whether to deliver a movie using progressive download, streaming, or broadcasting? It’s an important question for you, and since GravityLab’s business is delivering your content to your audience with the best possible user experience in mind, it’s an important question for us, too.
All all of the major streaming media codecs, both audio and video, can be delivered as progressive downloads. Streaming is limited to sound, video, and text. Broadcasting is further limited to compression schemes and quality settings compatible with real-time capture and compression.

Progressive download works even when the bandwidth is not sufficient for real-time playback; it simply buffers incoming data and delivers delayed playback. However, since it is simply a web server delivering your content through the HTTP protocol, many simultaneous demands for that media can result in a poor audience experience with significant buffering while the player waits for the content from the server. The back end infrastructure of the GravityLab content delivery network provides client / server negotiation for delivering the content in a timely, efficient manner for the best possible audience experience. This is important, since your online user’s patience, speaking in statistical averages, is about 4 seconds before they move on.
Streaming movies do not store a copy of the movie on the client computer, making them inherently more difficult to copy without the consent of the movie’s owner. This can be an important consideration, and is one reason why people choose streaming over progressive download.

Streams take up a specified amount of bandwidth, whereas HTTP file downloads proceed as quickly as the connection allows. It is therefore easier to manage the bandwidth usage of a streaming server than of a web server delivering progressive-download movies. With the proliferation of high speed internet connections at home, and because the vast majority of the US workforce has high speed access at work, delivering video content at predefined multiple bit rates (streaming) makes sense.
Broadcasting allows you to deliver coverage of live events as they happen, or to provide real time “chat” between computers. GravityLab provides live video broadcasts that can scale up as your audience grows.
To sum up, if your movie includes live coverage, you must use broadcasting. If bandwidth management and copy discouragement are paramount considerations, streaming may be your best choice for stored content. If bandwidth is not a concern, you want users to be able to receive you media regardless of connection speed, and you don’t mind if users obtain the actual copies of your audio and video content on their computers and portable devices, progressive download may be viable.

Using a Windows Media Server vs. a Web Server :

A Windows Media server is often the best way to stream media because Windows Media Services is designed specifically for that purpose, and all Windows Media components work together to enhance the end-user experience. Intelligent streaming, for example, involves Windows Media Encoder, Windows Media Services, and Windows Media Player.

This section compares the features of a Windows Media server and a Web server and describes the best way to determine which option is right for you.

Comparing server features
The features of each type of server are compared in the following table.

Table 2. Comparison of features for streaming Windows Media-based content

The following list describes each feature. If you are interested only in the features that a Web server can provide, then Web server streaming may be the right option for you.

• Stream through most firewalls. Firewalls are special servers that filter information that flows between the Internet and private networks or intranets. Many firewalls are set up by default to block data that isn’t from a Web server—data such as a Windows Media stream. Firewalls can be reconfigured to allow this data into the intranet. Alternatively, Windows Media servers can be configured to stream using the same protocol as Web servers, HTTP.
• Stream content with Digital Rights Management. Content that has been packaged using Microsoft Windows Media Rights Manager can be streamed or downloaded from either type of server. Windows Media Rights Manager helps content owners distribute licensed digital media over the Internet with superior audio quality.
• Fast Streaming. A feature of Windows Media Services that allows for a combination of streaming, downloading, and caching to provide the best user experience. Fast Streaming includes Fast Start, which downloads the first few seconds of the content at as high a bit rate as possible, so the wait to start playing is reduced; Fast Cache, which uses available bandwidth to cache as much content as possible ahead of playback; Fast Recovery, which sends error correction data with the data packets instead of waiting for an error to occur; and Fast Reconnect, which enables the server to automatically restore connections that are lost.
• Stream without downloading. Content from a Web server is downloaded. If Fast Cache is enabled on a Windows Media server, content might be cached to enhance playback. However, this feature can be disabled if you want your content streamed only.
• Broadcast (live). Web servers can only host on-demand content (files). A Windows Media server can host content for on-demand delivery or as a broadcast. Broadcasting enables you to stream live content (events that occur in real time), and files and playlists that are played back from the server. Some examples of broadcasting are streaming live radio and television signals, and Internet radio stations.
• Intelligent streaming. As mentioned earlier, this feature requires an interaction between a Windows Media server and Windows Media Player to optimize the stream for the current available bandwidth.
• Optimized for streaming Windows Media content. Windows Media Services was designed for the special requirements of streaming media. For example, Windows Media Services handles resources on a computer better than a Web server when streaming. A Windows Media server is capable of delivering more concurrent streams on a given computer by making more efficient use of a computer’s CPU and network bandwidth. A Windows Media server sends data at the same bit rate as the content. A Web server on the other hand does not control the bit rate at which it sends a stream. Consequently, two or more concurrent streams from a Web server could saturate a network’s bandwidth.

  Files are streamed from a Web server by using a method called progressive downloading. This means that a file plays as it downloads to the user’s Internet cache. This can be a concern for users, because digital media files often consume a large amount of hard disk space. Also, a user cannot seek to different parts of the content, until the entire file is downloaded.

• Indexing. This feature provides end users with a means of fast-forwarding and rewinding through a file that is being streamed, which requires interaction between a Windows Media server and Windows Media Player.
• Administering and logging. You can control how a Windows Media server manages live content and files, and monitor overall system activity in real time. You can also create detailed logs that include data such as individual client connection information and server events.