Government Information Preservation Working Group

1
Government Information Preservation Working Group

• December 16, 2003

2
Obsolete and Endangered TapesSource 2003
Cornell University Library, Digital Preservation
Management
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
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
Sony 8mm data cartridge QG-112MStorage capacity
2.5-5GBApproximate dates in use 1990-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
Fujifilm DG-90M DDS cartridgeStorage capacity
2.0 GBApproximate dates in use 1993-present
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
3
Obsolete and Endangered Disks 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 600Mb Dual-Sided rewritable Approximate
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
4
User-Removable Digital 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
5
Digital 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)

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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/g
  uidance/selecting-storage-media.pdf

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Digital Preservation

• Strategy
• Preserve what?
• ? To what?
• ? Now what?
• Future access

8
Considering CDs, DVDs?

• Whats to consider?
• Life expectancy
• Quality variations
• Interoperability/compatibility
• Robustness

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Factors that affect Disc LE

• Type
• Manufacturing quality
• Condition of the disc before recording
• Quality of the disc recording
• Handling and maintenance
• Environmental conditions

10
Maximizing Disc Usefulness

• Care and Handling
• Consider environmental influences
• Physical handling
• Storage conditions
• Labeling
• Cleaning

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CD, DVD Landscape
12
CD vs DVD Construction
13
Double-Sided DVDs
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Care and Handling of CDs and DVDs

• A Guide for Librarians and Archivists
• Co-Published by NIST and CLIR
• NIST Publication
• http//www.itl.nist.gov/div895/carefordisc/CDandDV
  DCareandHandlingGuide.pdf
• One-Page Reference from the Guide
• http//www.itl.nist.gov/div895/carefordisc/onepage
  .pdf
• CLIR Publication
• http//www.clir.org/pubs/abstract/pub121abst.html