VNC stands for Virtual Network Computing. It is, in essence, a
remote display system which allows you to view a computing
'desktop' environment not only on the machine where it is running,
but from anywhere on the Internet and from a wide variety of
machine architectures.
Many of us at ORL, for example, use a VNC viewer running on a PC
on our desks to display our Unix environments which are running on
a large server in the machine room downstairs.
What makes it different from other systems?
For this simple mode of operation, you could achieve a similar
effect by installing an X server on your PC. The important factors
which distinguish VNC from other remote display systems such as X
are as follows:
* No state is stored at the viewer. This means you can leave your
desk, go to another machine, whether next door or several
hundred miles away, reconnect to your desktop from there and
finish the sentence you were typing. Even the cursor will be
in the same place.
* It is small and simple. The Win32 viewer, for example, is about
150K in size and can be run directly from a floppy. There is
no installation needed.
* It is truly platform-independent. A desktop running on a Linux
machine may be displayed on a PC. Or a Solaris machine. Or any
number of other architectures. The simplicity of the protocol
makes it easy to port to new platforms. We have a Java viewer,
which will run in any Java-capable browser. We have a Windows
NT server, allowing you to view the desktop of a remote NT
machine on any of these platforms using exactly the same
viewer. (The NT server is not multi-user - see the
documentation). We developed VNC to give us
platform-independence after the success of our Teleporting
system, which was purely X-based.
* It is sharable. One desktop can be displayed and used by several
viewers at once, allowing CSCW-style applications.
* It is free! You can download it, use it, and redistribute it under the
terms of the GNU Public Licence.