Digital Preservation

Maruja De Villa Lorica
Paper written in Spring 2009

Introduction

This paper aims to provide enhanced understanding of digital preservation as an integral part of project planning for a digital imaging initiative. It will a) present the definition and rationale for digital preservation, b) discuss strategies towards digital preservation, and c) identify some institutions implementing digital preservation strategies.

Definition of Digital Preservation

Digital preservation refers to series of managed activities undertaken to ensure continued access to digital resources for as long as necessary (Alemneh and Hartman, 2002). It is essentially about preserving access over time (Digital Preservation Coalition). Likewise, it also refers to actions required to maintain access to digital materials beyond the limits of media failure or technological change (van Horik, 2005).

Rationale for Digital Preservation

The purpose of digital preservation is to maintain the ability to display, retrieve, and use digital collections in the face of rapidly changing technological and organizational infrastructures and elements (Cornell University Library, 2003).

There are many reasons for the need to preserve digital materials. Technology obsolescence of hardware or software is a major concern. It is generally regarded as the greatest technical threat to ensuring continued access to digital material (Digital Preservation Coalition).

Likewise, storage media can simply decay or malfunction, a process known as bit rot, which can lead to serious losses of information. This can affect digital data to varying extents, from single character omission, to scrambling of information, or to a major loss of data (Grindley, 2009).

Organizational issues like withdrawal of funding and general institutional instability are valid concerns for digital collections. Organizations merge and fold, and as a result, digital collections and whole data sets can become ‘orphaned’ as institutional priorities, interest and incentive to deal with digital materials change (Grindley, 2009).

Strategies toward Digital Preservation

A number of digital preservation approaches are being implemented to address the problem of digital objects not being accessible in the future. These strategies include preservation, emulation, and migration.

The technology preservation strategy is concerned with the preservation of the original software and hardware that was used to create and access the information. It is based on preserving the technical environment that runs the system, including software and hardware such as operating systems, original application software, media drives, and the like (van Horik, 2005; Digital Preservation Coalition).

The technology emulation strategy involves the re-creation of the technical environment required to view and use a digital collection. This is achieved by maintaining information about the hardware and software requirements so that the system can be reengineered. Through this strategy, future computer systems emulate older, obsolete computer platforms as required. Emulation is the process of imitating obsolete systems on future generations of computers (van Horik, 2005; Digital Preservation Coalition).

In the digital information migration strategy, digital information is re-encoded in new formats before the old format becomes obsolete. Its purpose is to preserve the intellectual content of digital objects and to retain the ability for clients to retrieve, display and use them considering the prevailing technology changes (Digital Preservation Coalition).

Migration involves transferring digital information from one hardware and software setting to another or from one computer generation to subsequent generations. Migration can also be format-based, to move image files from an obsolete file format or to increase their functionality. For example, migration has been used for electronic text, image, and database applications by the computing industry and a number of data archives and centers for decades (Grindley, 2009; van Horik, 2005; Digital Preservation Coalition).

Institutions undertaking Digital Preservation

A number of organizations are implementing a wide range of activities related to the preservation of digital objects. These include libraries, archives, and to some extent, museums.

Within the library community, the Research Libraries Group (RLG) carries out activities under the caption ‘Long term retention of digital research materials (van Horik, 2005). For example, the University of North Texas has began digital imaging and preservation projects in 1997 and has developed partnerships with Federal and State agencies to house digital collections (Alemneh and Hartman, 2002).

Some of the Digital Projects at UNT Libraries include the Government Documents Department Project namely a) Federal Documents Projects (CyberCemetery), b) State Documents Projects (Texas Register ,Gammel‘s Laws of Texas, Texas Electronic Depository Library Project), and Portal to Texas History Project. It also includes digital preservation initiatives for the Music Library, Archives Collections, and for the Dissertations and Theses.

Archives around the world are also spearheading work on digital preservation. The European ERPANET project, whose partners originate mainly in the archival world, is a European Initiative to establish a virtual clearinghouse and knowledge base in the area of preservation of cultural heritage and scientific digital objects. In the Netherlands, the project ‘digitale duurzaamheid’ (digital longevity), initiated by the Dutch National Archives and the Ministry of the Interior, is testing alternatives for the digital archiving of government documents (van Horik 2005).

In Australia, the PANDORA (Preserving and Accessing Networked Documentary Resources of Australia) project has successfully established an archive of selected Australian online publications, developed several digital preservation policies and procedures, drafted a logical data model for preservation metadata, and outlined a proposal for a national approach to the long-term preservation of these publication (Cornell University Library, 2003).

Museums and other cultural heritage institutions are also utilizing digital technology to create digital surrogates of rare, unique and valuable collections. A few are now implementing digital preservation for their digital collection.

Conclusion

Digital preservation is a vital component in digital imaging. It is huge task that requires concerted actions among international, national and local institutions. Preservation strategies and policies should be put in place; otherwise, most of the digital data produced today may not be usefully accessed by future generations due to technological obsolescence, data loss and other concerns.


References

Alemneh, and Hartman, C.N. (2002). Meeting Digital Resources Preservation Challenges: University of North Texas Libraries Initiative. PowerPoint presentation at the LITA Conference, October 13, 2002.

Cornell University Library. (2003). Moving theory into practice: digital imaging tutorial. Retrieved March 5, 2009 from: http://www.library.cornell.edu/preservation/tutorial/contents.html;
http://www.library.cornell.edu/preservation/tutorial/preservation/preservation-01.html

Digital Preservation Coalition. Preservation Management of Digital
Materials: The Handbook (www.dpconline.org/graphics/handb). Retrieved March 5, 2009 from
http://www.dpconline.org/docs/handbook/DPCHandbookDigPres.pdf

Grindley, N. (Feb2009). Saving for the future. Research Information, Issue 40, p13-14, 2p. Retrieved March 5, 2009 from Library, Information Science & Technology Abstracts with Full Text.

van Horik, R. (2005). Permanent pixels: Building blocks for the longevity of digital surrogates of historical photographs. The Hague. (PhD Dissertation). Retrieved March 6, 2009 from http://www.knaw.nl/publicaties/pdf/20051103.pdf