Digital Preservation in Grids and Clouds: A Middleware Approach

Digital preservation is the persistent archiving of digital assets for future access and reuse, irrespective of the underlying platform and software solutions. Existing preservation systems have a strong focus on Grids, but the advent of cloud technologies offers an attractive option. We describe a middleware system that enables a flexible choice between a Grid and a cloud for ad-hoc computations that arise during the execution of a preservation workflow and also for archiving digital objects. The choice between different infrastructures remains open during the lifecycle of the archive, ensuring a smooth switch between different solutions to accommodate the changing requirements of the organization that needs its digital assets preserved. We also offer insights on the costs, running times, and organizational issues of cloud computing, proving that the cloud alternative is particularly attractive for smaller organizations without access to a Grid or with limited IT infrastructure.