Grid(Lab) Grid Application Toolkit

Core grid technologies are rapidly maturing, but there remains a shortage of real grid applications. One important reason is the lack of a simple and high-level application programming toolkit, bridging the gap between existing grid middleware and application-level needs. The Grid Application Toolkit (GAT), as currently developed by the EC-funded project GridLab, provides this missing functionality. As seen from the application, the GAT provides a unified simple programming interface to the grid infrastructure, tailored to the needs of grid application programmers and users. A uniform programming interface will be needed for application developers to create a new generation of "grid-aware" applications. The GAT implementation handles both the complexity and the variety of existing grid middleware services via so-called adaptors. Complementing existing grid middleware, GridLab also provides high-level services to implement the GAT functionality.

We present the GridLab software architecture, consisting of the GAT, environment-specific adaptors, and GridLab services. We elaborate the concepts underlying the GAT and outline the corresponding API. We present the functionality of GridLab's high-level services and demonstrate how a dynamic grid application can easily benefit from the GAT. All GridLab software is open source and can be downloaded from the project web site.

Grid technology is widely emerging. Still, there is an eminent shortage of real Grid users, due to the absence of two important catalysts: rst, a widely accepted vision on how applications can substantially bene t from Grids, and second a toolkit of higher-level Grid services, tailored to application needs. The GridLab project aims to provide fundamentally new capabilities for applications to exploit the power of Grid computing, thus bridging the gap between application needs and existing Grid middleware. We present an overview of GridLab, a large-scale, EU-funded Grid project spanning over a dozen groups in Europe and the US. We rst outline our vision of Grid-empowered applications and then discuss GridLab's general architecture and its Grid Application Toolkit (GAT). We illustrate how applications can be Grid-enabled with the GAT and discuss GridLab's scheduler as an example of GAT services.