Structural Research And Design Of 3-layer Database System Based On Web Data Transmission

Along with the fast development of computer and network technology, the management information system should provide remote-sharing for various business data of enterprises. Consequently, the scale of the system is enlarging and the complexity becomes higher and higher. The original two-layer C/S system architecture can not meet the needs in data sharing, concurrent, flexibility, safety, etc. The three-layer/multilayer C/S system architecture is more flexible, and has many advantages, such as course managing, database connection sharing, thin client, high security and so on. While the B/S architecture has excellent ability of cross-platform, it can be realized under various platforms such as Windows, Linux and UNIX, and this architecture have simplified the requirement of client access.Although the expressway of our country has now already partially adopted informative-management, nearly every system is the two-layer architecture which is used in LAN. The expressway company is widely spread and has complicate network forms. The two-layer architecture can not fit this circumstance very well. This paper is based on the mixture structure of C/S and B/S, combined with distributed system development technology such as CORBA, DCOM and J2EE, studied the mixture structural system based on HTTP protocol data transmission, and the realization in the expressway management system. The research of this paper has important meaning for the further raising of the expressway informative management of our country. The research content of this paper is:1. The structural pattern of management system. The advantages and disadvantages of each structure are analyzed. Also applied both the C/S and B/S structures into management system at the same time, fully developed the advantages of these two structures.2. The mainstream technology of distributed development: CORBA, DCOM and J2EE. The application and characteristics of major technology for distributed system development are analyzed and discussed.3. The design and realization of mixture structure of B/S and C/S that based on HTTP protocol data transmission architecture. HTTP protocol can go thorough mostfirewalls. As a supplemental way of system, HTTP protocol has extended the application scope of C/S to Internet.4. Adopting abstract class and interface technology to realize the packaging of modular. That makes the software more modularization, and increases code re-usage, flexibility of modular installation and flexibility of system.