The main objective of DILIGENT is to create an advanced test-bed that will allow members of dynamic virtual e-Science organisations[1] to access shared knowledge and to collaborate in a secure, coordinated, dynamic and cost-effective way.  This test-bed will be built by integrating Grid and Digital Library (DL) technologies. The merging of these two different technologies will result in an unprecedented level of functionality and will lay the foundations for a next generation e-Science knowledge infrastructure. The DILIGENT infrastructure, which is based on high bandwidth networks and empowered by OGSA-compliant Grid services, will be able to serve many different research and industrial applications. The test-bed will be demonstrated and validated by two complementary real-life application scenarios: one from the culture heritage domain and one from the environmental e-Science domain.

- To open up Grid technology to a broad range of research and industrial communities.

The project will involve a number of distinct user communities as part of its experimentation, and it is expected that many others will join and use the DILIGENT infrastructure upon its completion. The experimentation carried out in these diverse user-driven application contexts will make it possible to test, validate and demonstrate both the power and the limitation of the Grid, and it will also stimulate the take-up of Grid technology in these areas, thus fostering its future wider deployment. 

- To broaden the diffusion of digital libraries, which are so far restricted to large organisations, by supporting a cost-effective digital library creation and operational model.

The DILIGENT infrastructure will maintain a network of existing content and application resources on Grid enabled technology and will introduce a new digital library development model characterised by low costs and sustainable delays. A virtual research organisation will be enabled to dynamically create and modify its own digital library by specifying a number of requirements on the information space (e.g., publishing institutions, content domain, document type, level of replication) and on the services (e.g., service type, configuration, lifetime, availability, response time). A reliable and secure digital library that satisfies the given requirements will be transparently instantiated and made accessible to authorized users through a portal. Many virtual digital libraries, serving different user communities, will be active on the same, shared Grid resources at the same time. The composition of a digital library will be dynamic since it will depend on the available and registered digital library resources and on many other quality parameters such as usage workload, connectivity, etc. This development model will make it possible to avoid heavy investments and radical changes in the organizations setting up these applications, thus fostering a broader use of digital libraries.

- To promote cross-fertilization between the digital library and Grid technology domains that will foster synergies and advances in both the areas.

The techniques for solving typical digital library issues, such as interoperability, ontology integration, workflow optimisation, content-based automatic selection, etc, will certainly provide useful insights for the development of Grid services. The high computational power that is offered by the Grid paradigm will promote the development of many new digital library user functionalities related to multimedia documents. In particular, functions like content feature extraction, summarization, automatic content source description, etc. on video, images, and sound, which are based on complex and time consuming algorithms, will become viable with a reasonable performance. Furthermore, the techniques for data replication and security handling developed in the Grid area will contribute greatly to the definition of new digital library preservation techniques.

[1] Virtual organisations are dynamic groups of individuals, institutions and resources, possibly remotely distributed, which are virtually grouped together to achieve a common goal.