Research And Implementation Of The C / S Structure Of The System Of Communication And Multi-user Technology

In recent years, Client/Server structure was widespreadly adopted in many applications. It is an entirely new kind of computing pattern compared with mainframe-centric pattern. It not only increases the robustness of an application but also makes fully use of various resources on the network. In the process of building application of C/S structure, we have made a thorough study on the communication method in C/S structure and the multi-user technology on server.1 On the basis of analyzing and comparing the distributive mode and applied mode of C/S structure, we produce the method of building applications of C/S structure and establish the base for the construction of this kind of application.2.Electric document management system is an application based on C/S structure. The user can access and manage the electric document database running on UNIX server through the multi-document-interface.(1)Network communication is the basis of application of C/S structure and its reliability and efficiency are very important. We realize high speed and reliable communication between Windows95 client and UNIX server by means of orient-connected and double link path based on TCP/IP protocol.(2)Multi-user is a basic demand of application based on C/S structure. Countering the diversity of application environment, the thesis produce two methods for the server to solve the request of users: single process and multi-processes. After analyzing and comparing, we select the multi-processes method to handle the requests of many users and construct a server structure which has a large capacity of lots of users, enormous data and high response speed.(3)In order to realize the mass-user technology in system of C/S structure, we must solve the conflict problem caused by the subtasks on server when they are fighting for those sharing resource. On the server of EECS, we solve the sharing resource conflict problem by way of semaphore which not only safeguards the consistent of system data but also increases the robustness of system.