It's digital, so it's safe...right?Information and communication technology has become an essential part of life. It is difficult to imagine education, work or entertainment without computers and networks. Yet reports of data loss due to outdated software and hardware have begun to appear at an increasing rate the past few years.
Anyone working with computers and digital files may have experience with converting documents into newer software versions, for instance with the transition from WordPerfect to Word. Conversions are usually carried out automatically with software delivered by the manufacturer. Apart from some minor errors, this does not create a problem for individual users.
When documents lag behind more than one or two versions, however, it may be very difficult to retrieve them. Besides, a few errors may not be a disturbing prospect for an individual user, but when thousands of documents or entire databases are converted, the consequences can be much more serious. Not only files run the risk of becoming obsolete. Hardware and carriers age as well. It is now virtually impossible to read a fifteen-year-old 5,25” floppy disk because the necessary equipment is no longer available. To preserve digital material for the long term more has to be done then just storing the bits.
What can we do about it?To prevent a digital black hole, the Koninklijke Bibliotheek (KB), National Library of the Netherlands, and the Nationaal Archief of the Netherlands started a joint project to research and develop a solution. Both institutions have a large amount of traditional documents and are very familiar with preservation over the long term. However, the amount of digital material (publications, archival records, etc.) is increasing with a rapid pace. To manage them is already a challenge. But as cultural heritage organisations, more has to be done to keep those documents safe for hundreds of years at least.
The National library and the National archive have been active in the field of digital preservation for many years. Various researches pointed out that basically two strategies exist to retain access to digital material: migration and emulation.
As migration alters the original document into a new version, emulation changes the current computer environment to mimick the environment in which the original document was rendered. For example, with migration an old Wordperfect document could be migrated to Word. This gives you the benefit of using the document in your current environment. However, it could change the document's content, layout or structure significantly which may be undesirable.
With emulation, the old MS DOS environment with WordPerfect as text processing software can be run. This allows the document to be viewed in its native environment and guarantees the user that the document's representation has not changed. This can be quite significant, especially for applications which can not be migrated.
Building an emulator for preservationAlthough many people recognise the importance of having a digital preservation strategy based on emulation, it has never been taken into practice. Of course, many emulators already exist and showed the usefulnes and advantages it offer. But none of them have been designed to be digital preservation proof. For this reason the National Library and Nationaal Archief of the Netherlands started a joint project on emulation.
The aim of the emulation project is to develop a new preservation strategy based on emulation. Our goal is to build an emulator that is durable and able to replace the Reference Workstation (RWS, a modern computer environment using MS Windows 2000 that is used as a reference for what the emulator should be capable of.). As a consequence, all kinds of digital material, like multimedia programs, databases and PDF documents will remain accessible in the long term. The emulation project started in April 2005 and ended in July 2007. From then on, development will take place within the European project on digital preservation: Planets.