Counting the Costs of Digital Preservation: Is Repository Storage Affordable?

Stephen Chapman
Weissman Preservation Center, Harvard University Library, Cambridge, MA, USA
Email: stephen_chapman@harvard.edu Web: http://hul.harvard.edu/ldi/html/steve_chapman.html
Key features References; Tables 1-2; Figures 1-4

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Contents 1 Introduction 2 Managed storage costs in Harvard and OCLC repositories 3 Cost gaps Case Study: Text Formats Case Studies: Non-Textual Formats Photographs Audio and Moving Images 4 Conclusion Acknowledgements References

Abstract

The Harvard University Library and the Online Computer Library Center, Inc. (OCLC) each manage centralized repositories optimized for long-term storage of library collections. Both organizations fully recover operational expenses by charging owners annual rates for managed storage services, regardless of materials use. The Harvard Depository assesses rates for analog storage per billable square foot. The OCLC Digital Archive assesses rates per gigabyte for storage of digital objects. Formats are significant, but not sole factors in determining preservation costs in these models. Owners’ definitions of content integrity and tolerance for risk, which can change over time, are also important variables in the complex equation of preservation costs and affordability.

Index of Tables

Table 1. Annual Costs for Managed Storage at Harvard Depository, by Format
Table 2. Annual Costs for Managed Storage at OCLC’s Digital Archive, by Format

Index of Figures

Figure 1. Relative Costs to Store Text “Masters”: Microfilm, Print, ASCII, and 600 dpi 1-bit Group 4 Page Image Formats
Figure 2. Relative Costs to Store Text Masters: Microfilm, Print, 600 dpi 1-bit, 300 dpi 8-bit, 300 dpi 24-bit Page Image Formats
Figure 3. Relative Costs to Store Still Image Masters (Copy Photographs) 35mm negatives; Photo CD (PCD) and TIFF master images
Figure 4. Relative Costs to Store Still Image Masters (Copy Photographs) 4 x 5 negatives and TIFF master images

Acknowledgements

The author would like to thank Dale Flecker, Taylor Surface and Simon Tanner for their careful reading and commentary to earlier drafts of this paper.

References

Ashley, Kevin (1999) "Digital Archive Costs: Facts and Fallacies". In Proceedings of the DLM-Forum on Electronic Records (DLM ’99), pp. 121-128
http://europa.eu.int/ISPO/dlm/dlm99/dlm_proceed99_03.pdf

DSpace (2002) "Format Support". MIT Libraries and Hewlett-Packard Company
http://dspace.org/mit/policies/format.html

Harvard University Library (2001) "Harvard Depository: About the Facility"
http://hul.harvard.edu/hd/about-hd.html

Harvard University Library Office for Information Systems (2001) "DRS Policy Guide", 5 October
http://hul.harvard.edu/ois/systems/drs/policyguide.html

Kingma, Bruce (2000) "The Costs of Print, Fiche, and Digital Access: The Early Canadiana Online Project." D-Lib Magazine, Vol. 6, No. 2, February
http://www.dlib.org/dlib/february00/kingma/02kingma.html

Lavoie, Brian (2000) "Benchmarking the Preservation Process for Electronic Scholarly Journals". DLF Fall Forum, November
http://www.oclc.org/research/staff/lavoie/dlf_1100.ppt

LeFurgy, William (2002) "Levels of Service for Digital Repositories". D-Lib Magazine, Vol. 8, No. 5, May http://www.dlib.org/dlib/may02/lefurgy/05lefurgy.html

Lesk, Michael (1996) "Substituting Images for Books: The Economics for Libraries". Symposium on Document Analysis and Information Retrieval, Las Vegas, April
http://lesk.com/mlesk/unlv/unlv.html

LOCKSS (2002) "Permanent Publishing on the Web. Lots of Copies Keep Stuff Safe"
http://www.lockss.org

NINCH (2002) "Preservation". In The NINCH Guide to Good Practice in the Digital Representation and Management of Cultural Heritage Materials, chapter XIV, Version 1.0 of the First Edition, October (Humanities Advanced Technology and Information Institute (HATII), University of Glasgow, and the National Initiative for a Networked Cultural Heritage (NINCH))
http://www.nyu.edu/its/humanities/ninchguide/XIV/

OCLC (2003) "Frequently Asked Questions: OCLC Digital Archive". OCLC Online Computer Library Center, Inc. http://www.oclc.org/digitalpreservation/services/archiving/digital/faq.shtm

OAIS (2002) Reference Model for an Open Archival Information System (OAIS), Blue Book, Issue 1, Consultative Committee for Space Data Systems (CCSDS). CCSDS 650.0-B-1, January. This Recommendation adopted as ISO 14721:2002
http://wwwclassic.ccsds.org/documents/pdf/CCSDS-650.0-B-1.pdf

Reilly, James (2002) "Preservation Strategy and Tools". Seminar on Preserving Photographs in a Digital World, Rochester, NY, August

Surface, Taylor (2002) "Supporting the Digital Collection Life Cycle: OCLC Digital & Preservation Resources". NELINET Digital Reality III Conference, October
http://www.nelinet.net/conf/digital/driii_02/surface.ppt

Weissman Preservation Center, Harvard University Library (2002) "NEH-Funded Brittle Books Microfilming: Harvard's Contributions: Project Statistics"
http://preserve.harvard.edu/news/microfilm/nehstats.html

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