Research Of A Lightweight Graphics Transmission Mechanism In Virtual Desktop Systems

Virtual desktop is more and more popular now. Existed virtual desktops include VDIand WebOS, they provide multiple features for users. However, VDI needs users to installclients and occupies high bandwidth with low efficiency. Although WebOS don’t needclients and is flexible, it has to rewrite all application programs.A new lightweight graphics transmission mechanism is presented to solve theseproblems. This mechanism enables people to achieve their remote desktop through a webbrowser at anywhere. Besides, they don’t need to install any software or plug-in, whatthey need is only a web browser that supports JavaScript. The most important thing is thatthis mechanism is efficiency, flexible and occupies low bandwidth.There are three advantages of lightweight graphics transmission mechanism. First, theinterfaces of specified windows, not the whole desktop, is transferred; what is transferredon site is composed of higher-level drawing primitives and these drawing primitives canbe simulated in the web browsers at client-side by JavaScript functions. At the same time,when the mechanism processes captured drawing primitives, it just transfers the drawingprimitives that cause the window interfaces changed. Furthermore, the standard controlsare simulated at client-side by JavaScript, so that users can still use the virtual desktopfluently when the network is not so good and the data has to be transfers can be less forthe interfaces of standard controls don’t need to be transferred.Lightweight graphics transmission mechanism can support all programs that arepainted by GDI system, including multi-window programs. The experiment shows that itcan reduce the data size by80%at average compared with VNC. Also, using thismechanism can bring less latency. In addition, text programs can still be operatedsmoothly when the network is not so good or even be disconnected.