Post on 31-Dec-2015
description
Fred Byers NIST 1
Government Information Government Information Preservation Working GroupPreservation Working Group
December 16, 2003
Fred Byers NIST 2
Obsolete and Endangered TapesObsolete and Endangered TapesSource: 2003 Cornell University Library, Digital Preservation ManagementSource: 2003 Cornell University Library, Digital Preservation Management
4mm DAT (TDK DC4-120 DDS2)Storage capacity: 1 - 4 GBApproximate dates in use: 1993- present
Fujifilm DLTtape III XTStorage capacity: 15GApproximate dates in use: 1994-present
4mm DAT (Verbatim DDS3 125M)Storage capacity: 12 GBApproximate dates in use: 1996- present
DC9135 QIC tape 1/4"Storage capacity: 1.35GApproximate dates in use: 1990-1995
G2000 (DC2000 compatible) Storage capacity: 40MbApproximate dates in use: 1990-1995
Sony 8mm data cartridge QG-112MStorage capacity: 2.5-5GBApproximate dates in use: 1990-present
Fujifilm DG-90M DDS cartridgeStorage capacity: 2.0 GBApproximate dates in use: 1993-present
DC6150 QIC-150Storage capacity: 150MbApproximate dates in use: 1990-1995
DC600A QIC-24Storage capacity: 60MbApproximate dates in use: 1990-1995
IBM 3480 cartridgeStorage capacity: 200MbApproximate dates in use: 1984-1994
1/2" 9-track ReelStorage capacity: Standard bpi recording densities of 800-6250bpi.It is estimated that over 90% of the world's data mine is still held on 9-Track
Fred Byers NIST 3
Obsolete and Endangered DisksObsolete and Endangered Disks Source: 2003 Cornell University Library, Digital Preservation Management Source: 2003 Cornell University Library, Digital Preservation Management
8" floppy disk (Radio Shack TRS80 Model II ) Storage capacity: 509,184 bytesApproximate dates in use: Late 1971-1981
5.25" floppy diskStorage capacity: 100KB-1.2MBApproximate dates in use: 1972-mid1980s
3 1/2" diskStorage capacity: 400K to 2.8 MBApproximate dates in use: 1982-present
Sony 12" Magneto Optical Disk (WDM-3DL0)Storage capacity: 3.2G Double-sided(WORM) Approximate dates in use: 1985-1992
Sony Magneto Optical Disk EDM-600BStorage capacity: 600MbDual-Sided rewritableApproximate dates in use:
Iomega 100 Zip disk Storage capacity: 100Mb Approximate dates in use: 1995-present
CD-ROM disc Storage capacity: 650MbApproximate dates in use: 1984-present
Fred Byers NIST 4
User-Removable User-Removable Digital Storage Media TimelineDigital Storage Media Timeline
Paper Magnetic Magnetic Magnetic Optical Optical Optical ???
(Infrared (Red (Blue/Violet Laser) Laser) Laser)
Punch Cassette 5 Floppy 3.5” Floppy CD DVD **
Card Tape Disk Disk Disc Disc Disc ???
l______________________l_____________________l_____________________l________________________l__
1970 1980 1990 2000 2005+? Future
** Blu-Ray Disc, Advanced Optical Disc, or other.
Timeline illustrates the changes in common “removable” storage media Source: Technical Advisory Service for Images (TASI) 2002, extended
Fred Byers NIST 5
Digital Preservation OptionsDigital Preservation Options Duplication (tape to tape) Media migration (tape to disc, disc to tape) Digital encoding format (old-to-new) Emulation (simulation of previous software) Hardware/software and OS preservation Outsourcing Wait and see, deal with it later Convert to analog (i.e. print documents,
microfilm)
Fred Byers NIST 6
Selecting Storage Media for Long-Term Preservation
An example scorecard, comparing some common media types
1 (does not meet the criterion) to 3 (fully meets the criterion). As a general rule, no medium which scores less than 12 should be considered.
Media CD-R DVD-R Zip Disk 3.5” Magnetic Disk DLT DAT Longevity 3 3 1 1 2 1 Capacity 2 2 1 1 3 3 Viability 2 2 1 1 3 3 Obsolescence 3 2 2 3 2 2 Cost 3 2 1 1 3 3 Susceptibility 3 3 1 1 3 2
Total 16 14 7 8 16 14
Source: THE NATIONAL ARCHIVES, Digital Preservation Guidance Note 2: Selecting storage media for long-term preservation, June 19, 2003. http://www.pro.gov.uk/about/preservation/digital/guidance/selecting-storage-media.pdf
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Digital PreservationDigital PreservationStrategy
Preserve what?
To what?
Now what?
Future access
Fred Byers NIST 8
Considering CDs, DVDs?Considering CDs, DVDs?
What’s to consider?
Life expectancy Quality variations Interoperability/compatibility Robustness
Fred Byers NIST 9
Factors that affect Disc LEFactors that affect Disc LE
TypeManufacturing qualityCondition of the disc before recordingQuality of the disc recordingHandling and maintenanceEnvironmental conditions
Fred Byers NIST 10
Maximizing Disc UsefulnessMaximizing Disc Usefulness
Care and Handling– Consider environmental influences– Physical handling– Storage conditions– Labeling– Cleaning
Fred Byers NIST 11
CD, DVD LandscapeCD, DVD LandscapeCD
CD-R, CD-RW, VCD
CD-ROMCD-DA, CD-I, CD+G,
DVDDVD-R General,
DVD-R Authoring,
DVD-RW,
DVD+R, DVD+RW,
DVD-ROM DVD-Video
DVD-Audio
DVD-RAM,
Fred Byers NIST 12
CD vs DVD ConstructionCD vs DVD Construction
Fred Byers NIST 13
Double-Sided DVDsDouble-Sided DVDs
Fred Byers NIST 14
Care and Handling Care and Handling of CDs and DVDsof CDs and DVDs
A Guide for Librarians and Archivists
Co-Published by NIST and CLIR
NIST Publicationhttp://www.itl.nist.gov/div895/carefordisc/CDandDVDCareandHandlingGuide.pdf
One-Page Reference from the Guidehttp://www.itl.nist.gov/div895/carefordisc/onepage.pdf
CLIR Publicationhttp://www.clir.org/pubs/abstract/pub121abst.html