Program Design And Implementation Of The Private Network Of The Prosecutorial System

With the quickly changing of technology, informationization is very important in the world economic area and to the development of society. The popularization and application of information network technology accelerate the progress of the current world. It is imperative and no time to delay for procuratorate, as supervisory departments of our country, to apply science and high-tech to their work, construct the information communication system and realize the automatization and modernization of official duties. So the criminal behavior can be beaten and the justness and unification of judicatory can be vindicated. The construction of the procuratorate information communication system includes the construction of hardware, software and networks. The construction of hardware is the premise, the construction of software is the base and the construction of networks is the kernel and the key.In view of the requirements of operations of the procuratorate, this paper discusses the technology selecting, the system designing and the system implementing solution of the Shandong province procuratorate special network construction project.This paper includes five parts. The first part is about the analysis of the system requirements. It discusses the concept of "combination of three networks" and the constructing background, application and bandwidth requirement of the system. The second part is about the analysis and comparison of major network technologies, including the comparison of ATM technology and IP technology, the analysis and comparison of frame relay and SDH/DDN, the analysis and comparison of the three phonetic technologies-VOATM, VOFR and VOIP. Now the VOIP technology is more and more perfectand popular. It is an effective way to attach the appropriate equipments to the special network to realize the inner telephone network, because it can enhance the security and save lots of charges for the use of telephones. The third part is about the structure design and the selecting of equipments of the whole network. By means of layered designing, the whole system canbe separated into three layers-core layer, convergence layer and accesslayer. With layered structure, it is easy to manage, expand the system, optimize the performance and fix the bugs. In order to keep thecompatibility of the equipments, all the equipments of the whole network have the same brand. Then the system can be managed and maintained easily. Every node can be configured according to the particular requirements, which can either assure the requirements of the network, or prevent the waste. The fourth part is about the design of voip network, including the structure and the QoS implemention. The fifth part is about the implementing of the system, the configuration and the management of the WAN.For a network system of the whole province, the layout and the management of the system are very important. Primarily, the proper layout of IP addresses and routing policy are needed, such as OSPT is an efficient routing method for large network. For VOIP system, the first thing is to make the code policy, according which to implement the configuration management. The second is to have perfect ways of management and maintenance. Such as, centralized management of networks, centralized configuration, allocation and dynamic management of bandwidth, user authentication and management of log files, etc.