Sam Goldwasser wrote:
"Dave D" writes:

"Brad" wrote in message
...
Hi,

From time to time, I come across an article about CD roms, etc.
What I have learned so far, CD-R (I use) is better than CD-RW for long
term storage of important data. Also, how they are stored can have
a bearing on their "life".

I keep CD roms in a dark cool location. To test the integrity of my
"burned" CD roms, I use "Finder" (search engine) I downloaded from
www.simtel.net. I "search" for a non-existant text pattern such as "i
don't
exist" in order to get "Finder" to read through every file on the CD rom
as a
way to check for corrupt data. Note: "Finder" has reported read errors on
some of my floppy disks. So far, no read errors were reported. However,
I
started burning CD roms about 4 years ago.

Is the integrity of commercial CD roms better than those I "burn" at
home?
How long can we expect to keep our CD roms, assuming they are stored in a
good
environment, before we begin to encounter corrupt data?
The simple answer to that seems to be 'no-one knows for certain'. I've read
10 and 25 years, but I take such claims with a pinch of salt. Just look at
laser discs, some of them were inherently faulty and developed 'sparkles' as
they deteriorated over the years. Unfortunately, it seems no data storage
medium is even close to perfect.

This is certainly true. I think the cool storage is fine but it should
also be dry. Dark probably doesn't matter that much as long as there
isn't much UV.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
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One thing i learned recently about optical disks disturbed me. I had
always taken the most care to protect the data side of the disk. I
found out that the most fragile side is actually the one with the label.
It's the one closest to the actual media. A scratch there--one which
might not even glitch a reader if it were on the other side--can expose
the metallic layer to corrosion.

jak