| With the rapid development of Internet technology, database technology has been widely used. At this rate, the traditional two-tier C/S architecture can't satisfy the users'needs any more. This traditional development model has already exposed its many shortcomings and limitations. For example, the problem of interoperability among different hardware platforms, different network environment, different databases, and representing its badly expansibility, inefficient resolution, lack of concentrative control, high maintenance cost, badly security when extended the application system which is based on the C/S model.To resolve the problem encountered in the two-tier model architecture, a three-tier development model has been brought forward in process of the development of management system of this item. By separating the core operation rules of this management system from client, and encapsulating these rules to be components, a independent middle-tier was constructed, thereby realized the"thin-client"model. In the three-tier architecture of this management system, the APIs what the middle-tier provide define a relative steady, high-level application environment and ensure the transparency of background database and the core operation rules to the client, therefore, the security and expansibility of this management system has been improved effectively, at the same time, the central control to the system has been boosted up and the maintenance cost has been reduced greatly.With the explanation of the definition of the information system, its possible physical structure, normal building methods, the concept of agent and its model, the concept of communication agent and the system of an executable method of build management information with port-communication agent were put forward in the need of the application of the information system.Because of the new requirement, during the implementation of this item, we developed it by two different tools in two different operation systems, but in the same model. After it put into use, we tested the aspects of basic functions, performance, do a contrast of these two implement methods. |
