Design And Implementation Of Video Conference System Based On Special Network Of Procuratorate Organ

With the rapid development of science and technology, information industry has been the common trend of world economy and community development. The popularization and application of network technology accelerate the rapid evolution of modern society. As a juristic supervisory organ, it has no time to delay for people's procuratorate to develop science and technology, strengthen the information construction, realize the office automation and modernize the case handling, in order to serve the procuratorate works by high-tech, strike criminal activity effectively, maintain the justness and unification of judicature.In our country, it has come through 10 years development for video and communication. At beginning, the video conference systems are only used in high agorae, such as government, finance and collectivize company. It mainly works in special network, and has very expensive cost, which is nearly millions and multimillions. Influenced by SARS of 2003, the video conference system has broken through the slow development phase and stepped into steady and rapid development phase, which has become an important approach for information communion.The construction of video conference system is not only the application of video conference technology, but also a systems engineering, which containing several subjects, such as network environment, analysis for carrying capacity of network equipments, choosing of MCU and terminals, technology of video and sound amplification. In practice, the problem of system design is how to carry out reasonable arrangement of video conference equipments according to our demands, for the purpose of an appropriate video conference system, which has scientific and trapeziform collocation, satisfies the operation demands and economizes the funds.Nowadays, there are several difficulties during the system design: 1.It is defective in guarantee for Quality of network Service (QoS). Because the traditional IP network was only designed for simple data traffic, which does not provide QoS guarantee, how to supply a great of real-time multimedia communication service in such network environment? 2. The second problem is the bandwidth of connect network. What kind of network bandwidth does user terminal provide? 3. Obstacle of network access. How to ensure the quality of video conference which is parallel with data and sound? 4. The problems such as increasing the mutual objects, advancing the video quality, enhancing the security and so on.This thesis expatiates the background and meanings of task, introduces the development status and related international protocol criterion of video conference system, as well as the key techniques and evaluatinon standard of constructing the system. After analysizing the requirement of system constructure in details, we adjust, layout, design and config the communication network, network security and Qos renewedly by way of testing the network environment. On this condition, we have completed the video conference equipments choosing, designed and realized a set of integrate video conference system based on special network of procuratorate organ in our province and the H.323 protocol, and developed a set of terminal software. Finally the conclusion and evaluation results of system are given.