The Concepts and Design of Distributed DBMS 1. INTRODUCTION A major behind the development of database systems is the desire to integrate the operational data of anization and to provide controlled access to the data. Although integration and controlled access may imply centralization, this is not the intention. In fact, the development works promotes a decentralized mode of work. This decentralized approach mirrors anizational structure of panies, which are logically distributed into divisions, departments, projects, and so on, and physically distributed into offices, plants, factories, where each nit maintains its own operational data. The shareability of the data and the efficiency of data access should be improved by the development of a distributed database system that reflects anizational structure, makes the data in all units accessible, and stores data proximate to the location where it is most frequently used. Distributed DBMSs should help resolve the islands of information problem. Databases are sometimes regarded, as electronic islands that are distinct and generally essible places, like remote islands. This may be a result of geographical separation, puter architectures, munication protocols, and so on. Integrating the databases into a logical whole may prevent this way of thinking.
To start the discussion of distributed DBMSs, we first give a de
