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Communication technology in the continuous development, in particular, the popularity of the network, many emerging applications continue to emerge, such as multimedia conferencing, distributed systems, computer work together. Which the multimedia conferencing gradually become a hot research. Domestic and international mainstream multimedia conferencing system mainly into two categories: multimedia conferencing system based on the H.323 protocol and the IP layer multicast-based multimedia conferencing system. These two types of systems there are some flaws, the former can not be the most efficient use of network bandwidth, while the IP layer multicast, there are some security risks. The context of this thesis is the view of this situation, in the National 863 Project \secure multicast conferencing systems. Relative to other conferencing systems on the market, the system has many advantages. First, it uses the VC of the end-to-end network architecture, which makes the quality of data transmission in the network to use the line network standards, and greatly reduces network congestion, packet loss and other phenomena occur; Second, the system uses the IP layer multicast technology for data transfer, conferencing platform does not use any hardware device, fully realized by the software, and significant savings in system cost; Finally, the system proposed by this topic the multicast security access policy as well as characteristics of the end-to-end virtual circuit architecture, effective The solution to most of the security problems faced by the IP layer multicast. In addition, the the multicast conferencing system also can be based on the operation of the IP layer multicast, can also be based on the application layer multicast operation, so that the flexibility of the software has been greatly improved. The whole system, and the network model has passed the test of Sichuan Software Evaluation Center. The paper is organized as follows: 1, according to a research position at home and abroad, the design goals of the system and describes the advantages have. 2, introduces the basic knowledge, including end-to-end VC multicast multimedia transmission as well as to understand in achieving programming basics. 3 describes the multicast conferencing systems need to achieve the basic functions, and, respectively, from the two branches of the IP layer multicast application layer multicast detailed analysis of the basic principles of the implementation of the various functions and achieve ideological. 4, the overall architecture of the system design and data flow analyzes a key part of the system: the thread pool. And a detailed description of the detailed design and implementation of various parts of the system. Finally, the system was comprehensive test and the results were analyzed, the results show that the system is run on the end-to-end network security architecture VC computational model, efficient and stable transmission performance and effective solution multicast security access and data security issues.
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