A User-Profile-Oriented Mediation Architecture for Very Large DataBases in a Dynamic Inter-Grid Context

In the last years, several distributed system paradigms have emerged, aiming at the share of a large amount of resources among a large number of users. The virtual organization concept in a multi-institutional context obviously presents numerous opportunities for business applications as well as for scientific ones. Nevertheless, the current trends seem to lead to several independent specialized grids in opposition to the early vision of one generic world wide grid. In such a context, large scale heterogeneous databases could be seen as several specialized databases hosted by different grids. The challenge is to allow users of these grids to access all databases with the same efficiency as if they were supported by the same grid. Our proposal is an overlay software architecture that is built on top of grid middlewares and acts in behalf of the user to facilitate the use of inter-grid databases. The proposed mediation solution deals with database heterogeneity and access rights management. It is capable of making decisions regarding the selection of resources and according to the hosting grid and to the infrastructure performances.