Database Middleware and Web Services for Data Distribution and Integration in Distributed Heterogeneous Database Systems

As the database environment changing, database is no longer accessed only by using SQL to communicate with DBMS as in the two-tier client-server architecture. In modern enterprise distributed systems, applications are developed and deployed as components in n-tier architecture. Database system is integrated with related applications and can only be accessed via interfaces provided by the application server or middleware. Moreover, in most of the middleware systems such as CORBA, J2EE, and RPC, clients and servers are tightly-coupled and client applications can only invoke methods by using proprietary communication protocols. As a consequence, data integration is no longer achievable by applying existing database middleware systems. What we dealing now are not just different DBMS vendors, dialects of SQL, or variants of data models, but also heterogeneous interfaces and communication protocols defined in various distributed paradigms. In this paper, we propose ADIM, an autonomous data integration middleware, with WebService for data integration in heterogeneous environments.