Video Content Delivery

There are two types of web video content delivery: Streaming and Progressive Download.

Streaming (broadcast or synchronous) video delivery

Streaming is the process of a broadcasting a video stream from a server to a client. It can be single client broadcast or multiple client broadcast - the process in both cases is identical and involves sending network packets over a protocol without flow control (usually UDP). Streaming is the only process of video broadcasting allowing live video to be delivered in realtime. An essential part of the process is the capability to skip parts (frames) of the video stream in case of a network error. This allows meeting the realtime criteria. This type of video delivery allows for both live broadcasting and on-demand video content delivery.

Progressive download (asynchronous) video delivery

The progressive download method is the process of downloading parts of the video and playing them as the download proceeds. This process involves buffering part of the video and then playing from the buffer. This method takes name from the launch of Flash Video platform but was created before all other major technologies. This method works better than streaming in some cases, like unstable connections and allows better video compression techniques due to its variable bitrate (VBR) and multiple-pass encoding. Progressive download is more efficient for short videos and allows for a very high quality content to be delivered (it would break a broadcast network. However this type of video delivery is strictly limited to on-demand video content delivery). This is also the preferred method for a pay-per-view solution because of the better quality and the possibility of packing the content in a unit.