Archived posting to the Leica Users Group, 2003/06/20
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This topic was the theme of an issue of "Communications of the ACM"
(Association of Computing Machinery) a few years ago. One of the
institutions that is struggling with the issues of digital storage
versus paper/film/microfiche/etc. is the Library of Congress.
An aspect of digital media which causes problems is: it is not
possible to read the data from it using "simple devices". You cannot
use your naked eyes or a magnifying glass to read the data from a
CD-ROM or a magnetic tape. You need a complex machine to extract the
data. What do you do when your complex machine ceases to function?
On top of that, you must have some knowledge of storage format.
To maintain a library, you have two choices:
1) Continuously copy the data to newer media and formats, before
the older media become unusable.
2) Maintain working examples of all machinery.
Option (1) becomes difficult as the size of the library increases.
A large crew of workers will be employed continuously copying the
data to the latest media, racing the clock before the older media
becomes unusable.
Option (2) is more difficult than you might first imagine. If you
say, "Just keep a closet full of CD-drives," you are ignoring the
possibility that the CD-drive might not connect to the latest
computer (for example, SCSI connections are fading away rapidly).
So, you must save an entire computer system, just to be safe. And
a copy of all of the operating systems and applications. And all
of the versions of those OS's and apps. And, considering that these
old devices might break down, how many instances of each system do
you save? You have to remember that the archival systems are not
mothballed in pristine condition, but are in constant use by
researchers and historians. Suddenly, the task becomes daunting.
Further, on option (2): When you find some interesting old content,
can you transfer it from the old system to a newer one? Do the
necessary communication and conversion protocols exist?
I have some 9-track mag tapes at home. They contain a copy of my
CS master's thesis work, which is a mere 13 years old. I have not
seen a 9-track machine for years. Even Hollywood hack directors
no longer show them in movies!
If you miss your last chance to transfer data from a vanishing
medium to a new one, you may lose it forever.
Mike
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