Optical Discs for Archiving Applications? Optical Discs for Archiving? Choosing an Archive Media
Define your needs regarding: Longevity Accessibility Price Capacity
Longevity
Longevity of Various Media
500
400
300
Years 200
100
0
Optical Media Other Storage Types and Access Time
Storage Type Media Access Time Primary storage Computer memory Nanoseconds Secondary Storage Hard drives/Optical discs up to 1 second Tertiary Storage Tape Library, Optical Jukebox 4–60 seconds Off-line Storage Tapes, Hard drives, Optical Disc minutes-hours Capacity vs Access Time
Source: World Technology Evaluation Center, Inc. Media Capacities/Cost of initial Purchase
Cost per GB
$0.05 $0.04 LTO Tape $0.03 Optical Disc $0.02 $0.01 Hard Disk $0.00 LTO Tape Optical Disc Hard Disk
Type Max Capacity Available Lowest Cost/GB
LTO Tape 3.2 TB (compressed) $0.022
Hard Disk 4 TB $0.047
Optical Disc 100 GB $0.031
*Cost/GB not necessarily based on largest capacity Selection Guide
Media Selection Scoreboard
Hard Linear Flash 1= Does Not Meet Criteria 3 = Fully Meets Criteria CD-R DVD-R Blu-Ray Disk Tape Memory
Longevity 3 3 3 1 1 1
Capacity 1 1 1 3 3 1
Viability (Error Correction) 3 3 3 2 3 2
Obsolescence 3 3 3 2 2 2
Cost 2 2 2 1 3 2
Susceptibility to Damage 3 3 3 3 2 1
Total 15 15 15 12 14 9 Pros And Cons Data Archiving on CD-R, DVD R or BD-R Media
.How long should Archive Grade Media last?
.What makes it “Archive Grade”?
.What is needed for best performance?
Archive Media: How long is long enough?
.Eventual migration to another media is inevitable
.Migration is expensive
.Keep your data on one media as long as possible.
.Start with media with the longest expected lifetime.
What makes it “Archive Grade” ?
.High Performance Recording Layer .Long-life Recording Layer .Oxidation Resistant .UV Resistant Factors That Affect Lifetime
Factors that affect disc life expectancy
Type of reflective layer Type of recording layer Manufacturing quality Condition of the disc Quality of the recording Handling and storage conditions All discs are not created equal: Pure Gold Reflective Layer
Disc failure often caused by reflective layer degradation.
Metal layer oxidization = unreadable disc
Gold never oxidizes
For CD-R and DVDR, MAM-A uses 99.99% pure gold Calculating the Lifetime of Optical discs
MAM-A uses ISO standards to test longevity:
ISO 18927-2002 for CD-R, ISO 10995 for DVD-R and Blu-ray. MAM-A DVD-R Longevity Longevity of MAM-A BD-R General Archiving Recommendations from NIST*
For archiving data on recordable discs, NIST recommends a gold metal reflective layer.*
*“Care and Handling of CDs and DVDs—A Guide for Librarians and Archivists” *National Institute of Standards and Technology Made in America
MAM-A is the only US manufacturer of Recordable Discs
ISO 9001:2008 Certified Reseller Margin
Cost for MAM-A Silver Plus Gold Archival disc: $1.20
Typical Selling Price: $2.00 No computer storage medium can be considered archival, irrespective of its physical longevity: technological obsolescence is inevitable and all media have limited life spans.
Source: National Archives Thank you!
Click on the link below to view the NIST Archiving guide
“Care and Handling of CDs and DVDs—A Guide for Librarians and Archivists”
There is additional archiving information at MAM-A.com