Research Of Transmission Technology Based On Virtual Network Computing

Video Conference System as the network multimedia comprehensive service platform is able to realize the loge-distance communication and work synergy for worldwide cooperative parterres and workmates. While the Video Conference only equipped with video and audio has not been able to meet the requirement of multimedia business applied area. Applied program share based on small quantity of exchange data and large information quantity will be the best enterprise collaborative tool, therefore it is respected highly by the fields in academia, telecom and software.Virtual Network Computing (VNC) is developed by a well-known European research laboratory named AT & T. It is a powerful remote desktop sharing tool that allows multiple clients views the situation in real time via the Internet server-side desktop and can be remotely operated.Traditional VNC adopts the default star-shaped Direct Connection Architecture with one computer acting as a shared server (VNC Server) to send shared data to the multiple clients (VNC Client) that is directly connected to the server. Client and shared server use a remote frame buffer (RFB) protocol to transmit data. RFB protocol needs to use multiple TCP connections to maintain a multi-client data sharing. When the clients increase to a certain number, because each client must transmit shared information in real time, the data that is sent by the shared server will increase several times over, reducing the real-time and availability of the system. In low-speed networks, as the bandwidth is limited, it is likely to cause network congestion. The client default encoder does not have the fault-tolerant capability, and the system itself can not discard the part sharing images in the data transfer to reduce the pressure on shared network server. This has resulted in the inadequacy in the use of traditional VNC application as sharing tools. This passage represents that VNC system has improved data transmission technology. On the basis of the star-shaped Direct Connection Architecture, it adopts the shared forwarding-controlled server. In the new scheme, the shared forwarding-controlled server forwards the shared data of the shared server to each sharing client, and data transfer process allows the loss of some of the shared data, at the same time, the server provides assurance mechanisms on data transmission to ensure that the shared data's analysis and display on the client's desktop. Experimental results showed that the data transmission technology improved can greatly reduce the shared server data transfer pressure to ensure the real-time and availability of the applied program. With the application of verification,the improved data system can make the transmission in real time and reliable, and make it possible that the VNC-based applied program is shared in low-bandwidth network.