All media server architectures can be looked at as being constructed from elements, or subsystems, of an overall system. In this chapter, we will be concerned with the front end of a specialized and unique system, the video server. While referring to this type of media server as simply a "video server," we understand and accept that video servers generally have inputs and outputs that include a media makeup of video, multiple audio channels, and usually at least some form of control interface.

A video server must essentially allow for the input, storage, and retrieval of video data in real time. Although the internal architectures of video servers will vary significantly from manufacturer to manufacturer, the basic principles of the video server remain essentially the same.

We can see in Figure 8-1 that the video server is comprised of an input side, a processing/storage section and an output side. Video and audio inputs and outputs can be of any flavor, including composite and component, analog or digital. The control and data I/O can be a mixture of timecode, machine control, or network interfaces.

Figure 8-1: Basic video server structure.

The makeup of the video server subsystems, including the interface to and between each subsystem, is the major factor in a video server's performance. The more a video server system is flexible in each of the subsystems, the higher the degree of applications it has.