Grid-based Heterogeneous Data Integration And Access To Technology Research

The development and widespread application of Internet Technology has caused various kinds of data resources' rapid expansion. But because data resources often are distributed in different network environments and use different data storage standards, different storage formats and different access methods, they isolate mutually and many detached information islands appear in the network environment. Along with the information construction's further advancement, more and more users and enterprises hope that they can share and process these data resources highly effective, transparently and reliably. Data integration is an effective method for collecting data with different sources, different forms and different characteristics and realizing the sharing of distributed, heterogeneous, autonomous data resources. The heterogeneous data integration technology to eliminate the detached information island has already become a hot researched topic in the current computer domain.Grid is one kind of new distributed computing platform, which has provided the mechanism of sharing and coordinating each resource, and it can organize the distributed heterogeneous resources to be a virtual computing system. Its architecture gradually realizes the standardization and normalization, and the Grid development group presents the relatively complete grid development toolkits, that provide many function components for developing the distributional application. The Grid technology has been gradually developing from the scientific research domain to the application domain and become an effective technology for solution complex mass data access and management. This article mainly studies the heterogeneous data integration and access based on the grid technology.Firstly, the article analyzed the present situation of domestic and abroad research on the problem of data integration, introduced the concept of heterogeneous data, its characteristic, data integration conflict and data integration principle; emphatically analyzed and compared each heterogeneous data integration method.Secondly, explained the definition of Web Services technology and its model, its protocols, its technical characteristic and its application; introduced the concept of the Grid technology, its architecture and the historical background of WSRF; expounded the concept of WS-Resource, its standard components and advantages.Thirdly, on the foundation of researching the Grid technology and Web Services technology, emphatically studied the architecture of Open Grid Services Architecture-Data Access and Integration OGSA-DAI, data service and its work process; through building the Globus environment, installed and deployed the OGSA-DAI software successfully and realized the access to different database systems using OGSA-DAI; given the existence flaw of the OGSA-DAI middleware. Finally, according to the characteristic of heterogeneous data under the current network environment, proposed the model of data integration and access system DIAS based on the Grid middleware technology; designed the DIAS system's core function modules, analyzed the DIAS system's key technologies, gave the realization of some DIAS system functions and carded on the performance analysis to the DIAS system from the overall.The DIAS system carries on data encapsulation based on Web Services, forms the loose coupled data integration method, and realizes the data "plug and play" function, which is with high extendibility. It has solved the system heterogeneous and grammar heterogeneous problems of heterogeneous data well and could satisfy the grid users' data access demand under the complex network environment.