Video and media servers - Applications, architectures and parameters

A video server, or media server, is a computer (or group of computers) that can store large quantities of audio, video or photo material in digital form and offer it on demand to one or more user-clients, either as a single stream or several simultaneous streams, or as files.

Media servers are at the heart of professional digital media production and distribution chains (audio – photo – video), and are now even finding their way into the home. The first part of this dossier gives an overview of these applications.

The second part describes the different architectures adopted, depending on the applications and performance targets. After a review of some computer architectures, a description of a video or media server based on a three-plane, four-class model is given, with some details on the storage subsystem. This will enable us to analyze today's increasingly complex audiovisual systems based on video and media servers.

Availability, reliability, scalability and compatibility - all important characteristics of a video or media server and the surrounding system - are discussed in detail in the final section.

To facilitate the reading and use of server-related documents, many terms have either been kept in English, or their French equivalents have been added. In the body of the text and illustrations, the abbreviation AV will be used for "audiovisual" or "audio and video", and the abbreviation A/V for "audio or video".

Unless otherwise indicated, most of the illustrations in this dossier are adapted from the referenced work. .

A list of abbreviations and acronyms is provided at the end of the article, to help you "decode" some of the terms used in this dossier and in referenced documents. For further information tables presenting an overview of some "server" and "storage" products.