Paper vs. CD Audit Trail

From: Keith Copenhagen <k_at_copetech_dot_com>
Date: Thu Nov 11 2004 - 12:44:28 CST

I looked into paper vs. cd as an archive of record.
Independent of any clear archive requirement (Other than surviving the
40 days before certification).

Best Case Lifetime :
Paper – Properly stored acid-free Archival sheet paper has a lifetime of
100 years.
CD – Projected lifetime of dyes using accelerated ageing studies is 100
DVD – No Data, I claim the underlying technologies are close enough to
model using CDs.

Purchase quality and handling are huge factors.

Derating factors :
Paper : Commodity Journal Rolls are probably 40-50% the quality of
             Rolling or Folding, causes some degradation when unrolled
(est. 10-20%).
         Rolling tension can put strong pressure on marks, (unquantified)
             Data is physical, and degrades over time.
I estimate up to 35 years for mostly successful first read, using best

CD/DVD : Quality varies widely although the newer faster (50X) are
culling out the lowest quality.
             Proper handling & reading should cause minimal degradation,
signed digital data can be migrated.
I estimate 20 – 60 years archival life, using best practices.

In addition, it is important to consider how to read the medium
Paper : Any custom paper roll reader has a very limited lifetime,
probably requiring re-invention to read older data. (Speaking of 8”
CD : CD/DVD reader technology has a limited lifetime, (CDs have been
around for about 30 years, that may be a one time best-case, although
the DVDs may carry the read capability longer than the “market
transition” ).
;: KODAK Writable CD and Photo CD Media. …follow[ing] an Arrhenius
model. That model predicts (at the 95% confidence level) that 95% of
properly recorded discs stored at the recommended dark storage condition
(25C, 40% RH) will have a lifetime of greater than 217 years.

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Received on Tue Nov 30 23:17:28 2004

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