Design And Implementation Of DAI Middleware Based On Web Service In Grid Environment

The grid is becoming a hot issue of the research in the distribute computing area in recent years.Its purpose is to construct dynamic virtual organization in the distribute,different structured and self-controled net environment,and to implement resource sharing and cooperation inside over self-controled areas.It is a necessary trend to upbuild an open and scalable grid data access and integration middleware system in order to fulfill the demand of large-scale and magnanimity data processing of the complex grid applications.On the base of general researching and analysising the demand of data access and integration(DAI) in the grid environment and combined with the characteristics of middleware technology,we bring forward the implementation strategy of DAI middleware with N layers application architecture,which is to build a middle layer software—Virtual Database System among different data resources and grid applictations.Users with authorization and authentication can dynamicly access and integrate distribute and all sorts of data resources in the grid environment by standard access interfaces and uniform data format supplied by Virtual Database System.The DAI middleware is built with Web Service technology,and predigest the programming pattern of DAI in the grid environment.It has shielded data access,database connection,data format conversion,data transmit and database integration etc,which are the bottom details concerned by users in its implementation, and satisfied users' sharing demand of the grid data resources in deed. At same time,it can be as a basic module for other advanced services.