Virtual Network Computing

NEW: The VNC system will be freely available from our website in the very near future. Watch this space for further details!
If you would like to be informed when VNC is released, please email us at [email protected].

The aim of the Network Computer (NC) is to allow access to centralised resources from simple, inexpensive networked devices. These act as clients to more powerful server machines connected to the network, which provide applications, data, and storage for a user's preferences and personal customisations.

We have taken this idea a stage further with a system called Virtual Network Computing (VNC). In VNC, server machines supply not only applications and data, but provide an entire desktop environment which can be accessed from any Internet-connected machine, including Unix workstations, PCs, NCs, and even PDAs, using a simple software Network Computer. Whenever and wherever a VNC desktop is accessed, its state and configuration (right down to the position of the cursor) are exactly the same as when it was last accessed.

The VNC system allows you to access the same desktop from a wide variety of platforms.

Many recent internet applications have focussed on how users, from their home computing environment, can communicate with the rest of the world. Our emphasis is on enabling the users, anywhere in the world, to communicate with their home computing environment. Members of our lab use VNC to access their personal Unix and PC desktops from any office in our building, and also to access these desktops from around the world on whatever computing infrastructure happens to be available in their current location. This includes, for example, public web-browsing terminals in airports. VNC thus provides mobile computing without requiring the user to carry any device whatsoever. As well as providing mobile access to personal desktops, VNC allows a single desktop to be accessed from several places simultaneously, making possible CSCW-style application sharing.

The technology underlying VNC is the remote framebuffer or RFB protocol. RFB is to Virtual Network Computing what HTTP and HTML are to the World Wide Web. It is the simplicity of the RFB protocol which makes VNC so powerful. Unlike other remote display protocols, the RFB protocol is totally independent of operating system, windowing system and applications. We currently have clients (viewers) for Win32, X and Java, and servers based on Windows and X. This screenshot from an early version shows a Unix desktop being accessed from a Java-capable browser.

The idea for VNC came from a fusion of two earlier ORL projects. The videotile is a networked display device which uses an early version of the RFB protocol as a way of displaying applications. The teleporting system allows applications based on the X window system to be mobile between different X displays on our local area network. VNC extends this notion to allow just about any graphical user interface to be accessible from virtually any display device.

For more information about VNC, read the Papers.