Digital Preservation Challenges, Infrastructures and Evaluations

To preserve digitally encoded information over a long term following the OAIS Reference Model requires that the information remains accessible, understandable and usable by a specified Designated Community. These are significant challenges for repositories. It will be argued that infrastructure which is needed to support this preservation must be seen in the context of the broader science data infrastructure which international and national funders seek to put in place. Moreover aspects of the preservation components of this infrastructure must themselves be preservable, resulting in a recursive system which must also be highly adaptable, loosely coupled and asynchronous. Even more difficult is to be able to judge whether any proposal is actually likely to be effective. From the earliest discussions of concerns about the preservability of digital objects there have been calls for some way of judging the quality of digital repositories. In this chapter several interrelated efforts which contribute to solutions for these issues will be outlined. Evidence about the challenges which must be overcome and the consistency of demands across nations, disciplines and organisations will be presented, based on extensive surveys which have been carried out by the PARSE.Insight project (http://www.parse-insight.eu). The key points about the revision of the OAIS Reference Model which is underway will be provided; OAIS provides many of the key concepts which underpin the efforts to judge solutions. In the past few years the Trustworthy Repositories Audit and Certification: Criteria and Checklist (TRAC) document has been produced, as well as a number of related checklists. These efforts provide the background of the international effort (the RAC Working Group http://wiki.digitalrepositoryauditandcertification.org) to produce a full ISO standard on which an accreditation and certification process can be built. If successful this standard and associated processes will allow funders to have an independent evaluation of the effectiveness of the archives they support and data producers to have a basis for deciding which repository to entrust with their valuable data. It could shape the digital preservation market. The CASPAR project (http://www.casparpreserves.eu) is an EU part funded project with total spend of 16MEuros which is trying to faithfully implement almost all aspects of the OAIS Reference Model in particular the Information Model. The latter involves tools for capturing all types of Representation Information (Structure, Semantics and all Other types), and tools for defining the Designated Community. This chapter will describe implementations of tools and infrastructure components to support repositories in their task of long term preservation of digital resources, including the capture and preservation of digital rights management and evidence of authenticity associated with digital objects. In order to justify their existence, most repositories must also support contemporaneous use of contemporary as well as “historical” resources; the authors will show how the same techniques can support both, and hence link to the fuller science data infrastructure.