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Re: MD Technology review

Subject: Re: MD Technology review
From: Walter Knapp <>
Date: Wed, 03 Jul 2002 20:10:15 -0400
Marvin Humphrey wrote:
> 
> Wild Sanctuary:
> 
> > MD and solid state formats certainly point the way to the future
> 
> Where can I find out more about the archival stability of solid state media
> such as flash memory cards?  They are too high priced to consider for
> permanent storage right now, but I'm curious.

They should not be considered archival, but only for short term. Pull
the recording off them and put it on optical disks of some kind for
archiving. They are reasonably reliable short term if not abused. I have
my doubts about them ever being other than a immediate short term
format. On top of that, they are very expensive media and tying up a
quantity in archiving would be very costly.

The most durable format reasonably available is the true optical disks.
50 years plus, some think hundreds. The ones I use of this are the 3.5"
opticals, currently available in several capacities up to over 2 gigs.
These have a protective shell, similar to floppy disks, in fact they
look superficially like a double thick floppy on the outside. And the
coatings are designed around durability as the primary function. On most
computers they can be used like a slow, removable HD. Their speed is
comparable to CD-R. These opticals are fully rewriteable, the spec there
being over a million rewrites. I have never had a disk or drive fail in
something like 6-7 years of use.

Next best is CD-R using quality media, it is another optical format. The
coatings are almost as good as the opticals, they are bigger and
unprotected in comparison to the 3.5" opticals, and of less capacity.
They also require special software and procedures to write, are write
only and are more suited for bulk archiving. They are, however, much
cheaper than optical disks.

The CD-RW's don't appear to be significantly different in durability
than CD-R's. But the formats to take advantage of rewriting never have
been well stabilized, so except using these like erasable CD-R's with
that format it's probably not a good idea to commit a big archive to them.

If you are recording to MD, it falls somewhere between those two groups
in reported durability, probably very close to the opticals. It does
have a protective case.

For all of these, probably the availability of the software and hardware
to read them will be the true limit of their durability. Unless computer
developments slow down a lot. It's going to be necessary to be on our
toes and keep transferring to keep up. If betting on the longest lasting
in these terms, it would be putting them on CD-R in audio CD format.

Walt



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