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NIST Releases Study Of CD/DVD Longevity
dirkin writes "The National Institute of Standards and Technology has released a preliminary study of the potential lifespan of CD-Rs and DVD-Rs. The PDF study is here. A good starting point for deciding what type of media to purchase to keep those backups and photos kicking around longer. (You DID buy the silver/gold alloy phthalocyanine CDs, didn't you?)"
the speed in which the CDR is burned sometimes it makes a difference, for the highest reliability I think 1x is the best.
My pr0n my precious precious prOn!
Take multiple backups and atleast have one backup on high quality CD-Rss not the 25c a piece ones.
Keep upgrading your Harddisk from time to time and backup data from old HD to new one.
for the last time people, I am "frodo from middle eaRTH", not "middle eaST".
Almost all of my no-name disks are dead after 3 years. Some of my verbatims are dead to. Hard disks at 1/gig now seems cheap compared to my dvd writer and 20c per gig disks. My bet is those optodisk-RW will be dead in two years.
treat them like a mushroom and keep them in the dark.
I have many CD-R discs that are still quite readable despite being 4-5 years old. On the other hand, I've seen a disk erase itself in less than a day when left in direct sunlight, and many disks will slowly degrade at light levels found in most human-occupied spaces.
Lots and lots and lots and lots and lots and lots of floppies.
Jonahweb.com has stuff.
Just put your stuff on an FTP site and let the world do the backup for ya.
Just backup to harddrives.
I'm using Araid99-1000 units in my computers, and backup is just replacing the slave drive (even while the computer is on and running).
The price for say, WD120mb drives are so cheap now that it is probably close to the cheapest, safest and most accessable backup format available.
Well - if you recall tape drives were the "big thing" in backup about 5-10 years ago. I have looked at 10 year old tape backups & they work just fine. Maybe we need to trust good old reliable tapes. Or the other (faster) solution would be external hard drive backups.
===> An eye for an eye makes everyone blind - MG
Just do what I do : buy a rack, install in front of your machine (under the DVD or CD-RW or somewhere) and back up all your important data (or your entire harddrive) to a separate harddisk. Prices on smaller models (40-60 gigs) aren't all that steep, and most people I know have trouble just filling up their 'small' 20 or 30 gig drives. A spare 60 gigger rackdisk will keep you satifsied for a long time... Alternatively you could also just buy an external fire-wire or USB harddisk, although I don't really have all that much experience with those kind of devices.
Simply buy twice the number of drives you need, and do an rsync between the two sets now and again. For added safety, get a friend with broadband and store the second box there. Then you are safe from fire, theft, drive crashes etc, with minimal effort to keep the backup up to date.
I've got a whole load of burned CD's that I created up to about 5 years ago.. and on varying quality of media, and a lot of them aren't any problem.
I suppose storage is the key thing, keep them in a dark cool place will help them last just that bit longer (unless you have a case of those little bugs that like eating the data layer).
Although they are of a similar tech, what about DVD recordable disks? I've got plenty of those now... but if I keep doing what i've been doing over the years and backup my backups onto newer media then I'm not too worried.
Just my $0.02
Are you local? There's nothing for you here!
This doesn't tell us much. It's almost a teaser. "Are you going to die tomorrow? The answer may surprise you. Stay tuned for News at 11." I have some CDRs that stopped working within days and others that have lasted over 4 years now--same brand from the same spindle even. I wonder if the full Dutch article gives specifics or if they found _any_ CDs that were still working fine after twenty months. The teaser seems to suggest that they're all terrible. I do know that I get fewer duds now that I use Toast than I did when I used "Easy CD Creator." Beyond that, I don't know anything that makes a difference. CDRs stop working. DVD-Rs are crazy fragile. Hard drives fail. Paper burns. Maybe my data wasn't supposed to last forever. Alex.
This article is quite inconclusive in my mind. There is nothing in it that describes the care given to the cds for the past 20 months (what cases, if any, they were in, the amount of light and heat they were exposed to, etc.) Also, there was no mention of the quality of the media they were burned on, nor the speed at which they were burned. Too many variables are introduced in the article to fairly say that cd media is not a viable backup alternative. It seems like decent advice to burn slowly and simply take care of your cds, they would last much longer.
Save it to film.
www.bannination.com Two things float to the top he
Since it was already taking 30 seconds to feed me the page, I might as well copy what I got..
CD-Recordable discs unreadable in less than two years
Posted by Dennis on 19 August 2003 - 14:33 - Source: PC-Active
The Dutch PC-Active magazine has done an extensive CD-R quality test. For the test the magazine has taken a look at the readability of discs, thirty different CD-R brands, that were recorded twenty months ago. The results were quite shocking as a lot of the discs simply couldn't be read anymore:
Roughly translated from Dutch:
The tests showed that a number of CD-Rs had become completely unreadable while others could only be read back partially. Data that was recorded 20 months ago had become unreadable. These included discs of well known and lesser known manufacturers.
It is presumed that CD-Rs are good for at least 10 years. Some manufacturers even claim that their CD-Rs will last up to a century. From our tests it's concluded however that there is a lot of junk on the market. We came across CD-Rs that should never have been released to the market. It's completely unacceptable that CD-Rs become unusable in less than two years.
On the image you can see the exact same CD-R. On the left you see the outcome of our tests done in 2001. On the right you see the same CD-R in 2003. The colours indicate the severeness of the errors in the following order; white, green, yellow and red whereas white indicates that the disc can be read well and red indicates that it cannot be read.
For those of you who are interested, the original Dutch article can be found here and in the September issue of PC-Active. Please discuss this subject in our Media Forum.
When modding "Informative", please make sure it both has a source and IS actually informative.
Or, rather literally translated into English: "Our sample shows that there is a lot of junk on the market. We have found cd-rs that should never have been for sale. Possibly it concerns rejected batches." Which suggests to me that the correct heading of this article should be: CD-Rs are like everything else: you get what you pay for.
What speed was used to write the CDs?
Were they all stored in the same place?
Were they all burned by the same CD burner?
Were they all burned from the same source (a single CD, hard drive, network, etc.)?
30 CDs sounds like an epidemic, but since they were all burned at the same time twenty months ago, there could be a lot of other reasons why all of these discs would go bad. If they were all burned at the same time, then they're effectively talking about one batch, regardless of how many different CD-R brands were used in that single batch.
Does the Dutch article cover this or is this just a scare story?
Take now into account earth's rotation and its magnetic field. It induces an albeit very slow movement of the molecules - the data layer degradation. The same effect causes btw certain currents in the Pacific oceans. While the movement is very slow and in the case of the ocean not very important, it does cause damage after a certain amount of time in the case of a CD-R. You should remember that the scale of the information storage units on a CD-R is in the nanometer range. The information is just "washed away" in an entropy-like effect.
However, you can slow this movement down. The molecular movement in the data layer is directed. So it can be reversed to a certain degree just be placing the CD-R the other way around. So, all you have to do is to mark the position of the CD-R in your rack exactly. And reverse it's position every month or so. This can increase to the lifetime of a CD-R about 150 percent. More can't achieved (in normal environment) because electric machines like your computer etc. create their own electro-magnetic fields. And the effects of these varing fields are much more difficult to negate.
BTW: the 100 percent wrong place to store your CD-Rs is on the top of your CRT.
Owner of a Mensa membership card.
Don't forget to have one or more off-site backups (encrypted in case they are stolen). I keep one off-site backup (on CD-RW) in town, at a friend's place, and swap it for a fresh backup every time I visit him. (Be sure to offer to do the same for your friends.) An out-of-state backup gets refreshed every time I visit my folks.
It's peace of mind knowing that if, heavens forbid, anything catastrophic were to happen to your place of residence, or if burglars were to take your computers and disks/tapes, then you would at least not have completely lost all of your critical data.
FWIW, I can't remember having a single CD-R go bad. I've had some scrathed ones which took a while to read because the reading drive slowed to a crawl, but I got the data nonetheless. I even recently found what must have been one of the first CD-Rs I've ever burned. Must have been from around '96 or '97, it had my backup copy of Duke Nukem 3D on it, among other stuff, and everything read fine (the disc was a Sony CDQ-74CN).
Did you know you can fertilize your lawn with used motor oil?
Back in the eighties, when regular CD's were first introduced that could be read by a standard computer (pc, mac, etc), the discs were fairly thick, and consisted of (iirc) from top down:
disc label
protective coating
data layer (usually pressed)
protective coating
Then at the end of the eighties, I don't recall exactly what year, but it was adopted by various cd makers till eventually all, the price of CD's dropped dramatically, almost in half.
The reason for this was the fact that the top protective layer was removed from the manufacturing process, leaving just the thin disc label and it's material to protect the data layer, barely.
I want to clarify that I'm talking about regular PRESSED cd's manufactured in bulk, and not dye layered ones, but the point is the same in both cases. By removing the top protective layer, it allowed manufacturing of CD's to drop in price dramatically.
I'm positive there have been other cost cutting measures used for dye layer CD's that the manufacturers have adopted over the years, such as cheper dyes that are affected faster due to exposure to sunlight, and so on.
It's not just about scratches or dye, but about the overall picture here. The manufacturers WANT to have built in obselesance. This gives them a nice steady flow of income when one has to contually burn his media archive every 2 years.
Food for thought anyhow. I thought I'd post about what I saw in the eighties, in case it was relevant.
user@host$ diff
I found it odd, though, as they said they couldn't tell the public their findings. This point stuck with me, but I forget the exact reason. Perhaps it is simply that it would influence the market? Wouldn't make sense to me: the taxpayer probably put up the funds for the tests and the public and the market would both benefit from the results. Maybe NIST got some industry money to do the test with the condition that the results be kept secret.
Anyway, it would seem they probably have done the same for CD-Rs.
I used to work for a company in Austin, TX whose speciality was optical drives (not CDs, but WORM mostly), and one of our customers was the National Archives. This was when CD-Rs were just coming out, and the NA was interested in a cost/benefit analysis of whether or not they could replace their expensive 14" WORM systems with cheap CD-Rs.
The first thing to understand is that WORM systems, true WORM systems, not the Magnetic-Optical pseudo-WORM systems, are built on ablation of material in the disc itself. In other words, you burn holes in the disc revealing a lower layer that is reflective. In the case of most discs, and Kodak especially, they were gold on the reflective layer for long-term stability. Various tests of accelerated degradation were performed in both climate stabilized and non-stabilized situations, and at worst, the discs were stable for 100 years before any error correction was necessary.
We decided to perform the same kind of evaluation of CD-Rs, and found that brand varied greatly. The best were stable for 3-4 years, the worst only 6-8 months if the climate changed dramatically. In addition, UV exposure had a radical impact on the life-span of the disc. Further research found out that the problem was the natural instability of the organic dyes that were used in the disc layers.
Basically, if the disc wasn't perfectly sealed (look at the work done in the referenced article, and how it starts at the edges), oxygen would get in and react with the dye, which would change it's characteristics relatively quickly. It doesn't take much before the dye structure collapses, and data becomes unreadable after a short period. While I suspect the dyes have gotten better over time, they're still organic last I knew, and still subject to degradation by contact with air. Quality control is the only thing that will get you anything here, and I suspect even the best dye-based discs can't make it past 20 years unless exposure to UV is totally eliminated.
What Kodak had developed was what they called "Century Discs", which were basically scaled down WORM discs, but in CD-ROM format. They were gold inside, non-reactive, and well made. They did, however, require a very expensive writer because they needed more power than a CD-R drive could ever hope to provide to force the burn away the spots. They were, however, readable in a normal drive.
That's just my experience, but everytime I've seen an organization talking about "archiving" on CD-R, I have issues with it. It's fine for "backup," where the data cycle is shorter, but true archival purposes (for example, financial data), it won't cut it. You either need to use WORM, or tape. Tape is, however, subject to problems over the cycles as well, witness the failing properties of 9-track tapes written by NASA in the 1970s (heard first hand, not sure where to find it written up). Linear-write systems are better than helical.
Just a few thoughts, but this is not an easy issue. You have to understand what you're storing, and how long it has to be readable before you consider an actual medium for storage.
used to include a study of glove compartment temperature cycles for their high end discs...
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
Holographic storage is almost here. Just more wasted tax dollars on a technology that will be obsolete by the time the media wears out (unless you own ancient cds).
You DID buy the silver/gold alloy phthalocyanine CDs, didn't you?
No, I've not ever ran across them, and it's not like they print the reflective layer and dye compositions on the side of the package. Mine are always green-ish.
(fp?)
"Alcohol, Tobacco, Firearms, and Explosives" should be a convenience store, not a government agency.
Mine will be kept on a real Hard Disk. What I have now is a 120GB, 7,200 rpm Maxtor HD, which has never disappointed me at all.
Discerning pr0n collectors choose silver/gold alloy phthalocyanine CDs.
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/
I still think that corn CDs are the best idea... you'll just need to reburn every once in a while.
It only becomes a problem if you're a big nacho fan...
I'm backing up onto my CDR now so I don't lose it. I advise the same to everyone else.
I look forward to over 2000 years of stable storage without data loss!
Yeah, right. Didn't you see Raiders of the Lost Ark? The Ark was full of dust.
At least you'll be able to melt some Nazis though.
The coolest voice ever.
actually, I was going through my legally obtained mpeg-4 backup CDs earlier this week, and found a number of Discs had irrecoverable errors on them, despite having been kept at room temperature, in cd sleeves, and having no scratches. The longevity of cheap to medium grade CD media is not nearly as high as you'd think.
that buying cheap crappy CD-Rs meant that your data died faster, but I had no idea how the degredation worked. What about the "armored" DVD-Rs from places like Datawrite? They're supposedly almost impossible to destroy. How well do they stand up?
With the study subjecting discs to extremes to cause them to fail, they've shown relative tolerance to certain conditions, but we still don't have "burn to these CDs and keep temp between 60 and 80, RH between 10% and 50%, and light to a minimum and they're good for 10 years" kind of numbers...
500GB of disk, 5TB of transfer, $5.95/mo
Yes, but corners weren't being cut to keep production costs to the bare minimum.
Ph-nglui mglw'nafh Gates M'dna wgah'nagl fhtagn.
I have some Kodak Gold CD-Rs stashed away for archival masters. I have no idea how long the DVD+Rs and DVD+RWs will last.
Mea navis aericumbens anguillis abundat
I just write mine down as ones and zeros on paper. It takes me a few months to do a full system backup, but it would take the government years to accomplish the same task. I figure I'll be saved by the statute of limitations by the time they figure out what I've been doing.
...papyrus. That, or clay tablets. Nothing else comes close. And I'm not joking.
Tubal-Cain smokes the white owl.
All those Netflix movies I've burned will essentially be worthless!
If someone says he and his monkey have nothing to hide, they almost certainly do.
...I guess I'm the oddball here. I've never thought of any of these media as permanent storage. In fact, I learned quickly very early on that all are susceptible to wear, damage or degradation. CDR/W and related tech are more a bandwidth-saving item or convenience item than anything else to me. The things that I need to save, I move to newer formats, usually multiple copies if it's important stuff.
I've yet to lose data to media degradation, however I once lost some important accounting data to a hard drive crash, followed by two ZIP disk backups that were killed by "click-death". One in a billion shot, I guess. Well, I didn't exactly lose the data, I had hard copies on paper, apparently the only semi-permanent storage media that's trustworthy.
Fred
"A fool and his freedom are soon parted"
-RMS
I suggest you get a little cozier with your browser configuration options...
In Capitalist America, bank robs you!
I wish they would test the Memorex black cd's. If you scratch the non-readable side of them, they are actually gold. I've been using these for the past year or two. The price is good on them, and I've had no problems.
Need Free Juniper/NetScreen Support? JuniperForum
As others have noted, the technologies used in the media are never printed on the packaging. Furthe, like many commodity items, the wrapper has nothing to do with who actually made the media. One spindle of Brand Y disks can be made by Manufacturer A, and the spindle twice its size, with the same labelling, also from Brand Y- will be made by Manufacturer Z. It is extremely difficult to be an educated consumer under these conditions.
It happens in lots of other places- gasolene is not "made" by Mobil; Mobil, Hess, Shell, Sunoco etc contract to area distributors. The distributors buy from whoever is the cheapest or distributes to their area; they slosh-mix any company-specific additives, if any, on the way to the station. Milk? Guess what- federal law requires that the bottling plant's registration number be printed on every bottle of milk. Next time you're in the store, notice how the brand name and generic store brand milk have the same prefix on that stamped number? Notice the brand name milk is pretty expensive compared to the store brand stuff? Dirty little secret of the milk industry, in plain view.
When I need CD-R/DVD-R media, I don't want to have to spend an hour sitting on some webforum reading posts to find out what the most reliable media looks like this week and where to buy it. I want to walk into a store, see "gold type cyno-whatever", see it's $2 more for a spindle of 20 than the other stuff, and walk out.
Though I'm sure there is collusion among manufacturers at the moment, it's only a matter of time before one manufacturer realizes they can market their product based on media type/chemistry thanks to this report educating buyers (the major PC mags will probably pick this up in an issue or two).
What bugs me is how bad my DVD-R disks SMELL. I have to hold the spindle at arm's length when I open the cakebox, and leave the room until the disk is done, because it reeks. I want to know what the hell makes it smell so bad...or, then again, maybe I don't...
Please help metamoderate.
Mitsui licensed the process to Kodak, and still sells the Gold/Silver CD-Rs under either the Mitsui or MAM-A trade names.
Older discussion: Say Goodbye To Your CD-Rs In Two Years?
afterdawn had a discussion on CD-R brands a while back. In short, go with Taiyo Yuden. And to identify Taiyo Yuden?
The biggest issue IMO isn't the media, but the readers. So what if your CD-RW is still readable in 20 years if you can't even find a CD-ROM around to read them with?
I still have tons of 5" floppy disks around, and I'm sure the data on them is usable, but getting it off is another story.
In fact, if I had enough space, I would back up my commerically manufactured CDs and DVDs, given the horror stories I've heard about their crappy longevity. The MP/RIAA wants you to re-purchase all the content they've sold you every 5-6 years. Screw 'em.
Computers are useless. They can only give you answers.
-- Pablo Picasso
did you ever go to the store and pick up a cheapo blank and a super high grade? you can feel the weight difference. you can also tell with older movies that are sold for under $10... they always weigh nothing. VHS tape is magnetic media (like audio tape)... generally speaking the heavier it is the better the quality. the higher quality ones also will last through more playings/recordings. i am not sure if either are better for archiving though.
with CD-R media i have heard some claims that the black ones are good (look like a playstation game) if they will go to people that have a tendency to leave disks all over their desk... the black plastic lens keeps harmful light off the media surface.
test brands yourself... leave a few on your dashboard through the summer and see what the sun and temperature swings do to them.
So what do i use for backing up data I want to keep for years?
CDr's now "suck".. I just moved alot of data off OLD hd's i had sitting around. They worked fine when i put them away but alot of them failed to spin up or had big time read errors. I thought moving everything to CDr would be the way to go.
I also use a RAID setup on netbsd with a few new seagate drives. Seems to be working fine but a good spike or other big hardware failer could knock the drives out... and just putting one drive away gets me back to my 1st problem.
So what do use?
I have to return some videotapes...
I uses 1's and lowercase l's. That always confuses the feds.
Dude, I think I can see my house from here.
(NOT a joke post)
Is it true with many things that reflect light, that the less light it throws back, the more it ABSORBS?
--meaning here probably, that absorbation is what degrades the medium.
I mean, I've had both "dull" and "blinding" discs, (some light-green one's that basically didn't shine at all once "shone on",) and the EXTREMELY reflective one's, that would practically blind you, to some extent.. --I mean, when angled towards a tungsten bulb, or flashlight, whatever..
-Get the drift? --Maybe this is of some importance, don't ask me.. I always go for 'the shiny' one's; as I've suspected them to be "better"..
A horse can't be sick, you know, even if he wants to.
DID NOT name this mysterious "D2" sample that was so much better than the others?
While it was not named, I think I can guess. Mitsui/MAM-A. They are stating now that their DVD-Rs are silver/phenothiazine based, which is the same chmistry that kicks serious butt with CD-Rs.
What will be interesting is to see if this chemistry holds up with Blu-Ray. The shorter wavelength may or may not be compatable with the dye.
Only problem is, the message gets corrupted really, really fast. Witness the Religious Right in America. Or medieval Europe. Or the tail end of the Roman Empire.
"Hardly used" will not fetch you a better price for your brain.
I store all my data in FBI digital case files. The government will obviously never have a system in place that can read them, so I'm safe.
I'm Rick James with mod points biatch!
and ordering numbers, folks. not many websites of manufacturers tell you what they're using.
the only one I can find right now in three websites (verbatim, imation, tdk) is that tdk uses metal-stabilized cyanine dye in their CD-Rs. that would make them a "c5" sample, which is fairly resistant to stray UV, but temperature/humidity sensitive. to me, TDKs sound just a little bright, but it's not bright enough to be a car-only disk.
verbatim used to boast of using blue azochrome dye, which In The Beginning was prized by burners who wanted accurate audio. verbatim blue is still out there in the "digital vinyl" series at least. that would be an "S1" or "S3", who knows which, which has some issues with both temp/humidity as well as strong UV. Sounded good and neutral.
what I haven't seen is the richer, "tube" toned deep green of Sony and 3M 2x/4x disks of the late 90s. never knew what it was chemically, either. I'd order a case of them if I could find 'em. no "scatter-shatter" sound on those disks.
the only thing I've had issues with are budget CD-Rs with a barely-visible green coating to this point. they go away in a dark, double-shielded player in a console in the car, and have shelf life issues in the house as well. After two years, they wouldn't even pass the pre-record test of the burner. Never again.
but I can't buy for known permanance, despite NIST, because they don't call out whose disks they tested. Hope somebody consumer-oriented gets an idea from this, and beats 'em up with brand names attached. there's going to be somebody out there who has used junk disks forever and never lost a one sitting open under the cat hair on the window ledge, so anecdotal evidence is, uhhh, not reliable. even mine.
if this is supposed to be a new economy, how come they still want my old fashioned money?
For backups and archiving, I use hard drives, period.
I change hard drives every few years, since there's a constant attrition rate, anyhow. Plus they just keep getting BIGER and CHEAPER every year.
to me, optical media are for sending data to others, not for gathering dust.
Is the data really gone, or is it simply the reader that can no longer handle the tolerances? Are the dots truly gone, or just harder to read? It could be that archivists and the rest of us need more tolerant, but slower-reading devices for when we have flaky discs.
Really, the big advantage stone tablets have is huge amounts of redundancy, but a very small amount of actual data. DVDs could have multiple repetitions of the data on different parts of the disc for fault tolerance.
Ooh, a sarcasm detector. Oh, that's a real useful invention.
Useful info on a few of the manufacturers, thx. But seriously, are you really attempting to describe the performance of a digital storage medium with terms used to describe the way the stored data sounds? "bright", "good and neutral", "richer, 'tube' toned"?
The terms you use correlate to accuracy of reproduction of various frequency of audio. Audio stored on a CD (I"m not talking about CD with mp3 files on it) is stored as a sequence of samples... that is to say strictly as a time-domain function.
I can't think of any possible way that the performance of the medium could have an effect on the sound of the audio that could be remotely described by the terms you've used.
My understanding is that CD-RW and DVD-RW doesn't use an "organic" dye, but relies on some physical property of an alloy to determine a one/zero. Are CDRW even more or less susceptible to aging?
I recently starting going through some of my old CDR's and I noticed that 3 of my 4 CDROM drives had trouble reading a certain disc. I try a 4th drive (DVD+RW), and it reads it just fine. My guess is this means that the disc is starting to die, and now would be a good time to back it up again.
I have several old Kodak gold CDs recorded on an HP 4x burner about five years ago (about US$400 -- top of the line at the time) which have died. They were stored in an airtight plastic camera box with dessicant and rarely removed. Now the dead ones seem to have some sort of dull, milky film on the shiny surface. Cause of death is unknown. Their neighbors (the exact same gold discs in the same box) are still OK, but I am making backups while I can. You can't necessarily trust gold either :-(
Archivists make a mistake when they focus on the preservation of digital media instead of the preservation of the bits. Since bits can be copied over and over without degradation, they are potentially immortal. Academic disk-based storage systems like Oceanstore http://oceanstore.cs.berkeley.edu/ and commercial systems such as Centera and Permeon http://www.computerbanter.com/showthread.php?t=309 50 keep the bits safe using redundancy on multiple servers, geographic distribution, and continuous and automatic migration to new hardware. Just as in biology, the organism (storage cluster) lives much longer than the individual cells (servers).
I had a friend tell me his store was bidding on a huge job to convert hundred of boxes of documents to PDF by scanning the documents. They were going to make CD-Rs with the PDFs on them.
They were then going to dispose of the paper documents via shredding.
This is an oil company with 20+ years of records.
The people he was bidding against were basically of the opinion of: "oh, these things last forever. don't worry about it."
Whereas I thought, "I think CD-Rs have a 10 year or so shelf life in darkness with low humidity."
I figured you would some optical character recognition to put into a keyword database and RAID servers and all kinds of good stuff. Not to mention making copies of the copies every X years.
Not to mention the fact that you would wonder if Cd-rom drives and Adobe Acrobat will be around in 10 or 20 years.
I kind of wonder how many people will get bitten by this issue.
I think this has been discussed before on slashdot that due to our digital world, ironically if there was some sort of global catastrophe there would be very little record of our civilization in 100 years.
...but the really annoying thing about CDs/DVDs, is that you have no idea that they have failed. You'll only notice when you try to recover. And I haven't found any program that'll let you burn a RAID - Redundant Array of Inexpensive Discs. If you want additional redundancy, you have to meddle around with creating PAR sets and distributing them yourself.
One small thing, which I've yet to see but maybe some slashdotter can point me to - is there any way, under windows, to automagically mirror a folder on one drive, to another folder (on another drive). I don't mean a full RAID1 of the entire disk, but the few 100mbs that are crucial. Sacrificing 160GB HDD space just for that seems like overkill.
Kjella
Live today, because you never know what tomorrow brings
Several people have suggested the idea of storing media in the fridge or freezer. This is not something to be done lightly. Yes, the colder temperatures would, all other things being equal, reduce the rate of chemical reactions. But in the real world, the fridge or freezer is a magnet for condensation and frost. If you put the disks in a freezer with auto defrost, then they can also be subjected to thermal cycling which is very bad. I am also dubious about a fridge/freezers suggested ability to survive fire given that they are often insulated with petrochemical foams that could be highly combustable or outgas harmful materials in a fire.
The humidity/moisture environment in a fridge/freezer is a complicated thing. On the one hand, water will condense on the evaporator coils which leads to a desicating effect. On the other hand, new moisture enters the compartment every time you open the door and through leaky gaskets. Sometimes the system desicates the contents of the compartment and sometimes it desicates the room only to condense or drip on the contents. And if the fridge is also used for food there can be vinegar drips from fermented food, mold, and other nasties. Each time the door opens, the contents are subjected to some degree of thermal cycling. When you remove a disk, it is also exposed to condensation.
The odds could be improved by putting the disks in a sealed container with some desicant, using a dedicated fridge, and maintaining the gaskets and drain.
I have encountered several people in the audio business describe the "Sound" of different types of CDs (as you do with "bright", "neutral", etc). However, I have yet to have a single one explain to me how a media type that simply describes waveforms through a binary series (1s and 0s) could possibly influence the sound produced, assuming the binary series is stored reliably in all of them. What impact would the media have on the waveforms? And WHY?
The only audible result from different brand of media, from what I understand, would be the vibration due to poor balancing, thickness, or other physical determinates of the vibrations of actual CD as it spins.
It was too much of a hassle to find the right one, so I transferred everything to HD. About 10 or so CD's were irrecoverably damaged. Some had faulty areas but were mostly readable.
Nowadays you should just buy a couple of 160+ gig HD's to store this kind of stuff. CD just does not have the capacity or ease of use or longevity, and DVD is not much better.
DVD drives in particular seem to be very picky about what they can read - I have 5 DVD drives only 2 of which read DVD+R's burned with HP NC8000, for example.
'Once scientists, even the dim-witted social scientists, get muzzled, the Western Civilization is finished.' - oldhack
In most of those cases though if you really needed the data, you could go to a data retrieval service and get it back, probably all of it in fact. I doubt you could get as much back from a CD-R mainly because once the dye fades I don't see much you could do. I'm sure these companies could try to work some magic but its not like the data is necessarily gone from the HD there's just no way to access it. Using CDs or DVDs to permanently back up important information is suicide, not to mention that its much more expensive. When I could buy a good 160 GB from Maxtor for $80, I don't see much point of using CDs and DVDs for anything other than short term backups and for using as actual CDs and DVDs.
From the article:
Do not be mislead by the numbers presented--they have little relevance to how CD-Rs are typically stored.
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