Video On Demand
Overview
With Video On Demand (VOD), the user can start the video when he
wants, make pauses, go forward and back in the video. It is of course
the best in video streaming and the dream for every user.
VOD is a very big consumer of resources for the server and the
network. VOD is unicast, not multicast : this means that the network and
server resources needed are directly proportional to the number of
clients.
The design of VideoLAN's VOD solution is very simple. The idea is to
do HTTP streaming, i.e. stream an MPEG video encapsulated in HTTP. The
regulation of the bitrate between the client and the server is done
automatically by TCP. With HTTP version 1.1, there is the possibility to
seek in a file downloaded, that's what we use to seek in the video.
On the server side
On the VOD server, you need a running Web server. For example,
you can use a Linux server running Apache. Other operating systems
and other Web servers should work too, but we have never tested.
Make your MPEG-1, MPEG-2 or MPEG-4 / DivX files available to the
clients on the Web server.
For example, we have a Web server whose DNS name is
localserver. On this server,
we put an MPEG file video1.mpg
which will be available to the clients at the URL
http://localserver/test/video1.mpg.
On the client side
Launch VLC, then click on the Net
button or select in the menu File / Network
stream, select HTTP and type the URL
http://localserver/test/video1.mpg.
VLC starts to read the stream nearly immediately and you can seek in the
stream, make pauses, etc... as if the stream was a local file.