NDSA:Digital Preservation Page -- draft outline: Difference between revisions
→Challenges of digital preservation: added par. on continuity, with reference |
→Strategies for digital preservation: SPD added text on migration & emulation |
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(generic, high level) | (generic, high level) | ||
#Refreshing, cyclical re-copying | #Refreshing, cyclical re-copying | ||
:''Refreshing'' is the transfer of data between two types of the same storage medium so there are no [[NDSA:bitrate]] changes or alteration of data.<ref>Cornell University Library. (2005) [http://www.library.cornell.edu/iris/tutorial/dpm/eng_index.html/ Digital Preservation Management: Implementing Short-term Strategies for Long-term Problems.]</ref> For example, transferring [[NDSA:Population census|census]] data from an old preservation [[NDSA:CD]] to a new one. This strategy may need to be combined with migration when the [[NDSA:Computer software|software]] or [[NDSA:Computer hardware|hardware]] required to read the data is no longer available or is unable to understand the format of the data. Refreshing will likely always be necessary due to the deterioration of physical media. | :''Refreshing'' is the transfer of data between two types of the same storage medium so there are no [[NDSA:bitrate]] changes or alteration of data. <ref>Cornell University Library. (2005) [http://www.library.cornell.edu/iris/tutorial/dpm/eng_index.html/ Digital Preservation Management: Implementing Short-term Strategies for Long-term Problems.]</ref> For example, transferring [[NDSA:Population census|census]] data from an old preservation [[NDSA:CD]] to a new one. This strategy may need to be combined with migration when the [[NDSA:Computer software|software]] or [[NDSA:Computer hardware|hardware]] required to read the data is no longer available or is unable to understand the format of the data. Refreshing will likely always be necessary due to the deterioration of physical media. | ||
#Replication | #Replication | ||
#Content preservation versus object preservation | #Content preservation versus object preservation | ||
#Migration vs. emulation | #Migration vs. emulation | ||
:Content preservation is generally achieved by one of two strategies, migration or emulation. Migration requires the repeated copying or conversion of digital objects from one technology to a more stable or current, be it hardware or software. Each migration incurs certain risks and preserves only a certain fraction of the characteristics of a digital object. Emulation as the second important strategy strives to reproduce all essential characteristics of the performance of a system, allowing programs and media designed for a particular environment to operate in a different, newer setting. | |||
===Identification of digital preservation communities=== | ===Identification of digital preservation communities=== |
Revision as of 21:31, 3 June 2012
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Definition of digital preservation
(generic, high-level)
Digital preservation can be understood as the series of managed activities necessary to ensure continued access to digital materials for as long as necessary. [1] It combines policies, strategies and actions to ensure access to reformatted and born digital content regardless of the challenges of media failure and technological change. The goal of digital preservation is the accurate rendering of authenticated content over time. [2]
Related topics that are not dealt with in this article include: intellectual property issues, privacy, selection for preservation, asset management, content management.
Challenges of digital preservation
(generic, high level)
Unlike traditional analog objects such as books or photographs where the user has unmediated access to the content, a digital object always needs a software environment to render it. These environments keep evolving and changing at a rapid pace, threatening the continuity of access to the content. Two separate strategies have been used to address the problem of continuity of access, migration and emulation. [ref= Becker,C et al. Systematic planning for digital preservation. International Journal on Digital Libraries Date: December 19, 2009, p. 134. (Int J Digit Libr (2009) 10:133–157 DOI 10.1007/s00799-009-0057-1)]
Strategies for digital preservation
(generic, high level)
- Refreshing, cyclical re-copying
- Refreshing is the transfer of data between two types of the same storage medium so there are no NDSA:bitrate changes or alteration of data. [3] For example, transferring census data from an old preservation NDSA:CD to a new one. This strategy may need to be combined with migration when the software or hardware required to read the data is no longer available or is unable to understand the format of the data. Refreshing will likely always be necessary due to the deterioration of physical media.
- Replication
- Content preservation versus object preservation
- Migration vs. emulation
- Content preservation is generally achieved by one of two strategies, migration or emulation. Migration requires the repeated copying or conversion of digital objects from one technology to a more stable or current, be it hardware or software. Each migration incurs certain risks and preserves only a certain fraction of the characteristics of a digital object. Emulation as the second important strategy strives to reproduce all essential characteristics of the performance of a system, allowing programs and media designed for a particular environment to operate in a different, newer setting.
Identification of digital preservation communities
(e.g., research libraries, national libraries, archives, governments, scientific communities, geospatial and observational data communities, architecture and design industry, video and film industry, broadcast industry)
Research library and “memory institutions’” digital preservation efforts
- History of engagement / involvement; relationship to institutional repository movement
- Organizations engaged in digital preservation planning (U.S. only? See Initiatives and Programs below), e.g., NDSA, PASIG, etc.
- Use cases (converted analog, born-digital documents, images, audio-visual material, data sets, observational data, electronic records, email, CAD-CAM content, digital games, mixed archival collections; digitization as sole preservation strategy for audio and moving images; computer software, dance performances; Web sites; social media archives; databases )
- Issues, assumptions, approaches, best practices [THIS SECTION COULD BE BETTER STRUCTURED]
- Data integrity, provenance, versioning
- Metadata considerations (types of metadata, objectives of metadata)
- “Dark archiving” versus access-oriented strategies
- Digital file format preservation issues
- Digital forensics
- Current and evolving technical standards (discussion)
- [branch to listing of individual standards and practices]
- “Trusted digital repository” framework
- History and current status (TRAC, Drambora)
- Issues addressed in current frameworks
- Metrics for assessment
- Certification strategies
- Digital curation
- Preservation of original hardware and software access systems
- Storage and OS considerations
- Sustainability and economic models for preservation
- Open source systems and tools (e.g., Fedora, JHOVE, PRONOM)
- Vendor-provided systems and tools (e.g., Rosetta)
- Preservation Initiatives and programs
- United States
- NDSA, LOCKSS, Hathi Trust, Portico, MetaArchive, CDL, Internet Archive, CRL, consortia, etc. -- mostly links to other articles
- United Kingdom
- Digital Preservation Coalition (DPC)
- Europe
- CASPAR, PLANETS, TIMBUS
- [Other countries, regions]
- United States
- Preservation-oriented conferences and meetings (e.g., iPres)
- Granting agencies supporting digital preservation
Other Preservation-Related Domains and Communities
[NOTE: The following are additional communities with somewhat different considerations and approaches in the area of digital preservation. While domain-specific published and defacto standards may in many cases be the same as those used in the research library community – and could be referenced from within the sections below -- best practices and use cases will differ. NDSA would not necessarily take any responsibility for these sections, so they are for now notional.)
- Digital preservation in the scientific and geospatial community
- Digital preservation in the architecture community
- Digital preservation in the domain of “personal digital preservation” (e.g., LC’s personal preservation initiative)
- Digital preservation in the broadcast media community
- Digital preservation in the audio engineering industry
- [Others contributed by other communities]
- ↑
- ↑
- ↑ Cornell University Library. (2005) Digital Preservation Management: Implementing Short-term Strategies for Long-term Problems.