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Data Storage

The Myth Of The 100-Year CD-Rom 671

Toshito writes "Are we putting too much faith in the ubiquitous "recordable CD", or CD-R? A lot of manufacturer claims 100 years of shelf life for a CD-R. But in real life, it can be much less. Expect failure after only 5 years... Personnaly I just discovered 6 audio cassettes with the voice of my late grandfather, talking about old times. These tapes are copies of reel to reel recorded in 1971, and they are still in excellent shape. I was thinking about digitizing everything, do a little noise reduction, and burning this on CD's, for my childrens and great grand-childrens enjoyment, but it seems that old analog tech from the '70 is more reliable than digital. The full story at Rense. Other links about the subject: Practical PC, Mscience, and an excellent reasearch by the Library of Congress (warning! PDF): Study of CD longevity, html version (google):Study html."
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The Myth Of The 100-Year CD-Rom

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  • Nonsense! (Score:5, Interesting)

    by Kris Thalamus ( 555841 ) * <selectivepressur ... AGOom minus city> on Thursday April 22, 2004 @01:27PM (#8940704)
    I was thinking about digitizing everything, do a little noise reduction, and burning this on CD's, for my childrens and great grand-childrens enjoyment, but it seems that old analog tech from the '70 is more reliable than digital.

    Record it to your HDD in an non-lossy format and store copies of it on various friends' and family members' computers. Back up frequently and your recordings won't suffer from the kind of decay and generation loss that analog tape does.
    • Re:Nonsense! (Score:5, Informative)

      by cuzality ( 696718 ) on Thursday April 22, 2004 @01:32PM (#8940772) Journal
      Well, the recordings *will* go through decay, but that's what the constant backing-up process is about. Your basic point is right on the money, though.

      The only way to keep bits in any kind of order and in good condition over a long period of time with the kind of technology available to the average consumer is to keep making multiple fresh copies before each individual storage media begins to suffer loss of data.
      • by Neon Spiral Injector ( 21234 ) * on Thursday April 22, 2004 @01:37PM (#8940831)
        What happens when the amount time it takes to transfer all the data from one medium to another is longer than the life time of the media on which it currently resides?
        • Re:Nonsense! (Score:5, Insightful)

          by Anonymous Coward on Thursday April 22, 2004 @01:55PM (#8941059)

          What happens when the amount time it takes to transfer all the data from one medium to another is longer than the life time of the media on which it currently resides?

          Then obviously you couldn't have copied all the data to the "current" medium in the first place.

          • Re:Nonsense! (Score:4, Interesting)

            by SEWilco ( 27983 ) on Thursday April 22, 2004 @02:46PM (#8941655) Journal
            What happens when the amount time it takes to transfer all the data from one medium to another is longer than the life time of the media on which it currently resides?

            Then obviously you couldn't have copied all the data to the "current" medium in the first place.

            • He might still be writing the current backup.
            • He might have such a huge amount of old data that the remaining life time is the problem.
              • Reports are that NASA has huge amounts of data on magnetic tape which is fading, and copying to new media will take longer than the remaining life time of the magnetic data. Obviously they need to start shipping out tape drives and tapes to volunteers who will have their computers copy tapes in their spare time, and let them see if they can find anything odd in the data at the same time; a Distributed Search for Earth Intelligence.
              • For years old films have been degrading faster than they have been copied to more stable media. Part of the problem is money, part is the time required for the delicate task.
          • Re:Nonsense! (Score:4, Insightful)

            by Detritus ( 11846 ) on Thursday April 22, 2004 @03:04PM (#8941923) Homepage
            Then obviously you couldn't have copied all the data to the "current" medium in the first place.

            Not true. The data could have been collected and recorded on the current media by multiple field sites, which may no longer exist, may have upgraded their recording equipment, or be too busy with current data collection projects to dupe media. You can easily end up with many thousands of tapes in a warehouse and insufficient equipment and time to copy them to new media before they rot. That's assuming you can get the funding for the work in the first place.

    • Re:Nonsense! (Score:5, Insightful)

      by Anonymous Coward on Thursday April 22, 2004 @01:42PM (#8940896)
      Whether CDs last a long time or not is really missing the point. The benefit of going digital is that the data can be backed up.

      If you're oriented on the media you're forever on the upgrade path. Should you move the collection to DVDs? But wait, blue light DVDs are right around the corner. It will never end.

      120Gbyte hard disks are getting cheap. This trend will continue. What you store something on will literally become unimportant. The only important thing that will remain is still: how well is it backed up?
    • by Anonymous Coward on Thursday April 22, 2004 @01:49PM (#8940985)
      "Real men don't use backups, they post their stuff on a public ftp server and let the rest of the world make copies." - Linus Torvalds
    • best bet... (Score:4, Interesting)

      by Byteme ( 6617 ) on Thursday April 22, 2004 @02:11PM (#8941258) Homepage
      ...is to cut your own vinyl [vestax.co.uk] and then play it on a laser turntable [elpj.com]. Isn't vinyl the preference for the Library of Congress [loc.gov]?

    • by SatanicPuppy ( 611928 ) <Satanicpuppy.gmail@com> on Thursday April 22, 2004 @02:23PM (#8941399) Journal
      The number of things that can go wrong with old magnetic media is so long I won't even go there. If nothign else, the magnetic tape will get old and brittle. It also stretches slightly when you play it, which could leave granddad sounding like James Earl Jones in a few years. Certain types of mildew love it. AAAAAA! Make a copy! Make a copy!

      Add to that the cost of replacing r2r tech, and you've got a scary situation. I agree with the parent. CD may not be the answer, but digital sure as hell is. I'd be super paranoid having anything I cared about stuck on old tape.
  • CD Rot (Score:5, Interesting)

    by Liselle ( 684663 ) * <slashdot@lisWELTYelle.net minus author> on Thursday April 22, 2004 @01:28PM (#8940715) Journal
    The story about the Rot of Death seems to come up every once and a while. My fun strategies for longevity:

    - If you can rub the top of a CD and have your finger come back silver, that's a bad sign. I avoid cheap CD-Rs. Sorry, CompUSA.
    - I burn at 2x, always, unless I am burning something that I don't care about. Someone showed me the difference in color, I was convinced.
    - Sticker on top = CD death.
    - Take care of your media. Had a friend who left a CD on the windowsill and forgot about it. Many months later, you could see right through it. Nice corrosion.

    I find it weird that anyone can stick a 100 year lifespan on a product that hasn't been around that long. I know that they have processes that supposedly accelerate the process and give you a rough estimate, but I am skeptical. Maybe they really are that durable, and people are just careless/cheapskates. You know what they say about malice and idiocy.
    • Re:CD Rot (Score:5, Funny)

      by TedCheshireAcad ( 311748 ) <ted@fUMLAUTc.rit.edu minus punct> on Thursday April 22, 2004 @01:39PM (#8940859) Homepage
      Ripping the reflective surface off CDRs is a good way to impress kids with shiny things. The only problem is, they then want to do it.

      While counselor at a computer camp, once I showed a kid how to rip the reflective face off a CDR with some duct tape, and he spread that information to all the kids. Little did they know that the dye underneath is toxic, and like 7 or 8 kids were puking up their lunch later on. I told the boss I had no idea what happened. :-\
    • Burning at 2x... (Score:5, Informative)

      by ajutla ( 720182 ) <ajutla at gmail dot com> on Thursday April 22, 2004 @01:45PM (#8940928) Homepage
      Although it seems like burning at a slower speed means that your data lasts longer, for some newer CDs burning at 2x might actually cause your data to be less secure. Most CDs sold nowadays are optimized for faster burns, say at 48x. The "fast" media doesn't handle slow burn speeds quite as well as older media optimized for 2x would.
    • Re:CD Rot (Score:5, Informative)

      by Wavicle ( 181176 ) on Thursday April 22, 2004 @01:51PM (#8941013)
      This is all true. You may not know the vast difference in materials used for CD's.

      If the CD feels sticky around the edges, it may (may) mean a low quality glue was used. It provides a potential path for fungus to migrate into your CD.

      Gold reflecting layers (very rare to find anymore) are the absolute best. Gold generally doesn't react with the stuff in the atmosphere.

      High quality archival stabilized dye layers are also hard to find anymore. Phthalocyanine was the absolute best last I looked (a few years ago) with an estimated stable lifetime of 200 years.

      A CD that you want to hold data for 100 years should have a quality glue job, gold reflective layer and Pthalocyanine dye. I know of only two brands that have ever been made to this quality. One was Kodak Gold (some marketing suffix here), but it went out of production several years ago. The other is Mitsui Gold, which cost about $1 each in 100 packs.

      And no matter how nice the CD manufacture is, it will not last unless properly stored. The three tenets of archival storage are: Cool, Dry and Dark. Don't leave your CD-R's on the shores of a tropical beach.
      • Re:CD Rot (Score:5, Informative)

        by bgalehouse ( 182357 ) on Thursday April 22, 2004 @02:08PM (#8941220)
        As of a few months ago you could certainly still get gold reflecting layers with Phthalocyanine dye, though you have to pay for it. I ordered 100 Mitsui gold's (now apparently called MAM-A) from dsgi [dsgi.com] for digital photo archival.


        I have to burn them at less than max speed, apparently the more stable dye requires more laser power. Otherwise no surprises so far. (knock on wood)

  • by Anonymous Coward on Thursday April 22, 2004 @01:29PM (#8940719)
    The 100 year CD-ROM becomes a 27 million year CD-ROM, and they plan to have their copyrights extended that far.
  • Solution! (Score:5, Funny)

    by Morgahastu ( 522162 ) <bshel ... fave bands name> on Thursday April 22, 2004 @01:29PM (#8940721) Journal
    Store them on a series of floppy diskettes. They have proven to be VERY reliable. ;)
  • Doooom(esday)! (Score:5, Interesting)

    by llamaguy ( 773335 ) on Thursday April 22, 2004 @01:30PM (#8940732)
    Factor that in with the project the BBC did in the mid-1980s (A digital Domesday book, designed to be a snapshot of life at that particular moment of time) that was unreadable withing 20 years because of the fast pace of technology and no way will CDs last 100 years.
  • by wren337 ( 182018 ) on Thursday April 22, 2004 @01:31PM (#8940744) Homepage

    Blank CDs in bulk are cheap. For archival stuff I make a new copy every 5 years. I have a bunch of scanned photos I don't want to lose, so I re-copied them all onto new CDs.

    You aren't supposed to write on the CDs either but I've not had any trouble with that, probably because I'm not trying to keep them very long.

    • I'd like to add that with the current progress of storage technology there is really no need to copy CDs to other CDs every five years. Instead you'll probably want to copy CDs to DVDs to HD-DVDs to whatever in order to save physical storage space more often than every five years. Thus refreshing will happen automatically as long as you do not lose the media.

      Losing and then finding media is of course the real problem as lost digital recordings do not get refreshed and may be destroyed.
  • by Guano_Jim ( 157555 ) on Thursday April 22, 2004 @01:31PM (#8940746)
    Rename the MP3s of your grandfather's voice to coors_twins_baby_oil.mpg and put it on Kazaa.

    Repeat every year with the current cover girls of Maxim, Stuff, or whatever men's mag suits your fancy.

    Guarantee you'll never be at a loss for a copy of dear old granddad.

    • Yeah but if I d/l that recording of his grandfather's voice, then his family will sue me for copyright infringement!

      -m
    • by BarryJacobsen ( 526926 ) * on Thursday April 22, 2004 @02:06PM (#8941201) Homepage
      Daddy, what's great-grampa doing with those ladies?

      Oh, sorry son. Wrong file. Don't tell your mother.
    • by bshroyer ( 21524 )
      It's actually a great archiving idea. Something along the lines of Freenet. Distributed, anonymous, redundant storage.

      Using P2P software, you supply:
      a) n bytes of data you want archived
      b) 10Xn bytes of free space to archive other people's stuff

      So you've got 1GB you want preserved forever? Supply 10GB to the network, and the software takes care of the rest. If a user drops out of the network, his "stuff" is purged after 30 days of inactivity, freeing up space for new participants.
  • I know lots of people that have "worn out" cd's. The first time I heard that, I thought they were kidding, but no... even if you take super great care of say, an audio cd, it will eventually wear out. It's especially bad if you keep it in the original plastic jewel case, and take it out each time -- my friend's rare Pearl Jam CD's are nearly scratched beyond playability, but he was able to extract the digital information before it got lost. What makes CD's better than tapes is that the 0's and 1's will always "be the same" logically, unfortunately the physical media wears out quickly with use. I prefer to think of CD's as a temporary storage mechanism for a permanent idea, like a sketch on newsprint. Once the newsprint disintegrates, you'd better hope you made something good with the idea... it doesn't mean the idea is gone, but the medium isn't like stone.
  • by thoth ( 7907 ) on Thursday April 22, 2004 @01:32PM (#8940766) Journal
    The danger in "old" storage formats is lack of machines to read them. Those tapes may be in good shape, and so might the data on an 8" floppy I have, but the 8" floppy is effectively lost to me because I don't have easy access to a drive that can read it anymore! The paper tape programs I "printed" out from a VAX PDP-11 are probably good (if I hadn't lost them years ago) but I can't get to a tape reader, etc.

    You almost have to make dozens of copies of data on a modern cheap format, and keep moving it forward.
  • First of all... (Score:5, Insightful)

    by unperson ( 223869 ) on Thursday April 22, 2004 @01:32PM (#8940771)
    How do you know there is no loss with analog?

    Analog quality loss is acceptable, because it results in static. Digital loss isn't acceptable, because (at least practically) it is a binary property...the CD works or it doesn't. Scratch the hell out of a record, and at least you still have something.

    We could build acceptable redundancy into digital backups, its just that most people think of it as wasteful. You know what though?... I have everything worthy of backup "backed up" in at least 3 places, one of which is always CD stored somewhere out of reach. Digital is better. Once you convert to digital, you can have zero quality loss with near 100% efficiency, you just have to want it that bad.
    • Re:First of all... (Score:5, Informative)

      by Neon Spiral Injector ( 21234 ) * on Thursday April 22, 2004 @01:47PM (#8940959)
      Have you ever head of Reed-Solomon? There is redundancy built into CDs.
      • Re:First of all... (Score:4, Interesting)

        by unperson ( 223869 ) on Thursday April 22, 2004 @02:26PM (#8941425)
        But I think the problem is that CD media doesn't have what most people consider "acceptable redundancy"

        When a CD ages, and the surface scratches, and the ink degrades, the data doesn't fade to yellow and get wrinkled like a newspaper, or it doesn't sound like its being pumped over a telephone like a record would, it is just gone. At least with analog data (especially newspaper) there isn't this working/not working parity...we can see the degradation and recopy the data before its too late.

        Of course we try to get around this by adding error detection/correction schemes, but I think the original post is about how (apparently) these aren't adequate.
  • by dankney ( 631226 ) on Thursday April 22, 2004 @01:32PM (#8940773) Homepage
    It's not exactly a fair comparison between CD-R and analog tape for audio. The audio tape isn't "more reliable." It just degrades differently.

    As the tape ages, the quality of the audio signal degrades dramatically, but because it is an analogue signal, it can still be deciphered by or ears.

    With digital medium, the audio never gets worse. As the media degrades, it just reaches a point where it isn't able to be deciphered as audio data.

    If you want to compare the mediums (magnetic tape vs. CR-R), data is probably a better place to do so. You can easily measure the amount of readable/unreadable data in bytes and make a fair, quantifiable comparison.
  • Storage Conditions (Score:5, Insightful)

    by EpsCylonB ( 307640 ) <eps&epscylonb,com> on Thursday April 22, 2004 @01:33PM (#8940775) Homepage
    In the wrong conditions, such as sunlight, humidity and upper surface damage, your CD-R will slowly turn into a coaster. "CD-Rs should never be left lying in sunlight as there's an element of light sensitivity, certainly in the poor quality media," says Stevenson. "I wouldn't rely on CD-Rs for long-term storage unless you're prepared to deal with them as recommended."

    Surely storing cd's correctly is the key, if the dye on a cdr fades after being kept in a jewel case at a room temperature fr 2 years then that is obviously very bad (and there could be some lawsuits in the future).
  • Redundancy (Score:4, Informative)

    by KalvinB ( 205500 ) on Thursday April 22, 2004 @01:33PM (#8940788) Homepage
    Keep original copies on the Harddrive, Cassette, ect and then make copies as needed.

    Tape isn't going to last forever. At least when it's digital you can easily transfer to new media without loss of quality.

    If it's really important you just need to make sure you keep ahead of obsolecence. Transfer the stuff to the new standard before the old standard completely goes away. There's always a transition period.

    Ben
  • 5 Years is accurate (Score:4, Informative)

    by nurb432 ( 527695 ) on Thursday April 22, 2004 @01:34PM (#8940790) Homepage Journal
    I have found most of my cdr's that are that age or older are starting to fail.

    Rather dissapointing the first time it happened.

    seems to be from several big brand names, so it must be a limitation of the Dye, not just a bad batch.

    But then again, it was designed to be written too ( i.e. physcially changed ) so how can one expect it to last forever?
  • by Anonymous Coward on Thursday April 22, 2004 @01:34PM (#8940802)
    The first link is to rense.com, a website that promulgates the theory that the US government is experimenting on us with "chem trails" emitted by otherwise innocuous-looking aircraft flying overhead. The webmaster at that site obviously has a very low threshold for rubbish, and no critical thinking ability!
  • by Pedrito ( 94783 ) on Thursday April 22, 2004 @01:35PM (#8940808)
    What's the deal? This same article with a slightly different look shows up every 6 months, it seems.

    Besides the fact that CDs DON'T have a 100 year shelf life, we've also discussed the CD eating fungus several times here, which for people in hot and humid environments (particularly, it seems, Mexico, Central, and South America) can reduce a CDs lifespan to months or a couple of years.

    And then you have the fact that rewriteables have an even shorter lifespan.

    One thing that's rarely mentioned is the fact that most CDs are defectively manufactured. I say this because the metalic layer between the plastic is supposed to be sealed. But the fact that the aforementioned CD eating fungus enters through the two layers of plastic says to me that CDs are generally defective in that they fail to properly seal this layer.

    I personally lost about 25% of my CD collection to this fungus over a 2 year period in Mexico, so I speak with some experience. These CDs were not abused. Most were in plastic cases, some were in sleeved carriers.
  • by avandesande ( 143899 ) on Thursday April 22, 2004 @01:35PM (#8940810) Journal
    Some of my first cds purchased in 86 (Are You Experienced and Electric Ladyland) are clearly losing sound quality.
    • by tuffy ( 10202 ) on Thursday April 22, 2004 @01:48PM (#8940974) Homepage Journal
      Some of my first cds purchased in 86 (Are You Experienced and Electric Ladyland) are clearly losing sound quality.

      Pressed CDs shouldn't be as vulnerable to bit rot as burned CD-Rs. But I can't understand how the discs would lose quality. One either gets a valid frame of redbook audio or not. I can understand that some of the frames might go bad (even to the point where the built-in error correction can't help) and lead to audio defects, but I don't see how the whole disc would sound different than before.

    • Actually, most of the CDs from that era sound horrible...digital mastering has come a long way since then, as has playback equipment. A disc from 2001 is going to sound much better than one from the late 80's.
  • Why 100 years ? (Score:5, Interesting)

    by da_reboot ( 683601 ) on Thursday April 22, 2004 @01:37PM (#8940832)
    I don't get this obsession with hoping to keep media for 100 years. Technically punch cards are forever. Do you still use them ? No, because their storage capacity is ridiculous by today's standard. In five years you will store your data probably on your solid-state 200 g key-chain.... move with the times..
  • FUD (Score:4, Interesting)

    by polyp2000 ( 444682 ) on Thursday April 22, 2004 @01:37PM (#8940834) Homepage Journal
    All this about CD's not lasting very long is just FUD by the RIAA. In the next few years or so they will want to bring out a new type of media so that everybody has to restock their cd collection with the new media format.

    Bottom line, buy cheap media then you will suffer the consequences. Buy decent media; buy a reputable brand and you can expect reasonable lifespan.

    Hey, and wasnt this a dupe? albeit one with a twist ?

    nick ...
  • by shawkin ( 165588 ) * on Thursday April 22, 2004 @01:37PM (#8940838)
    The BBC Library still uses vinyl records for long term audio storage. For some items they cut a lacquer master, plate the metal stampers on the lacquer and leave the metal stampers attached to the lacquer.

    They believe that this will preserve the audio for about 300 years and they say that vinyl is the only storage medium with a real and predictable life span.
    • I love vinyl... and believe me, the only thing that will make vinyl come back is when those vinyl turntables with a laser reader come down in price

      http://en.wikipedia.org/wiki/Laser_turntable

      8,000$ is just not within my disposable budget.

  • by Just Some Guy ( 3352 ) <kirk+slashdot@strauser.com> on Thursday April 22, 2004 @01:38PM (#8940847) Homepage Journal
    I've said this before, but it bears repeating: do not filter or otherwise "enhance" the audio files before you store them. Instead, save them losslessly, hisses, pops, and all.

    Audio processing technology will get better. Don't ruin your grandkids' heirloom recordings by using today's technology to permanently alter them.

    Make working copies and filter those as much as you want, but keep those masters pristine! Maybe somewhere in the background you can hear your grandma yelling at dear ol' grandpa to put that thing away and paint the house, and a clumsy run with an agressive low-pass filter will throw that data away forever. You have something really valuable; please take care of it for the future.

  • by Anthony Boyd ( 242971 ) on Thursday April 22, 2004 @01:39PM (#8940855) Homepage

    ...is not that the CDs will decay and become unusable. The real problem will be that the file formats of today will be replaced in 10 years, and will be a legacy file format only readable with a compatibility layer in 20 years. In 50 years, that CD will be unreadable. Of course, storing it in ISO 9660 format would offer some protection. If nothing can read the CD 50 years from now, you could at least fall back to the standard spec write your own code to read it.

    Oddly enough, I note that UDF is getting pushed as a replacement to 9660. So maybe even 9660 will be outdated faster than I expect.

    Will CD drives exist then? I certainly can't get an old cassette tape drive these days, and that's only been 20 years. Hmm. I think in 100 years, the decay of your CD will be only 1 of many problems.

    • by michael_cain ( 66650 ) on Thursday April 22, 2004 @03:22PM (#8942144) Journal
      The real problem will be that the file formats of today will be replaced in 10 years, and will be a legacy file format only readable with a compatibility layer in 20 years. In 50 years, that CD will be unreadable. Of course, storing it in ISO 9660 format would offer some protection. If nothing can read the CD 50 years from now, you could at least fall back to the standard spec write your own code to read it.

      Not just the format of the file system (your example), but the format of the individual files. Does anyone believe that, outside of a handful of people in museums, anyone will be able to read GIF files in 100 years? Or MPEG-1 compressed video? Or documents stored as Microsoft Word 97 files? I've worked with computers for the past 25 years, and have encountered all of the problems that people have mentioned in this discussion: tapes for which there are no drives available, tapes and disks which degrade to the point that they are unreadable, file systems on disks that are not supported by contemporary OSs, and individual file formats for which no software (or specifications) exist. I also have a box filled with the paper copies of 25 years' worth of writing, and even the oldest are in good shape and WORK. If they were especially valuable, I'd make another paper copy and put it in the safe deposit box at the bank.

      Audio and video are more difficult, since there's nothing as good as paper for them.

  • by jd ( 1658 ) <imipak@ y a hoo.com> on Thursday April 22, 2004 @01:40PM (#8940869) Homepage Journal
    • Avoid exposure to UV radiation. Keep locked in a lead casket when not in use.
    • To prevent chemical reactions from affecting the disk, keep chilled at -90' or so. Liquid notrogen is a useful cooling system.
    • Prevent scratches by always using ultra-smooth surfaces and clean-room environments.
    • To stop acids and other chemicals from the body attacking the CD, use those space-suits from the Intel commercials.


    Now, you can enjoy your CDs for a long time...

  • Simple (Score:3, Funny)

    by eclectro ( 227083 ) on Thursday April 22, 2004 @01:41PM (#8940879)
    Personnaly I just discovered 6 audio cassettes with the voice of my late grandfather.....I was thinking about digitizing everything, do a little noise reduction, and burning this on CD's, for my childrens and great grand-childrens enjoyment

    Go ahead and digitize everything. Then get yourself a couple of accounts at Gmail [google.com] when it becomes available. Then email the audio to yourself. You will have it forever then.

    Of course you will see a lot of google adwords for Geritol [geritol.com] and Ben Gay [yahoo.com], but nothing is perfect.
  • Oblig 'Me Too' Post (Score:5, Informative)

    by da3dAlus ( 20553 ) <dustin.grau@gm[ ].com ['ail' in gap]> on Thursday April 22, 2004 @01:43PM (#8940909) Homepage Journal
    I'm sure what I'll say has already been said, but I can certainly attest to the shorter-than-advertised longevity of CDR media. I recently had to pull some long lost files off of CD's I burned back in the college days, probably 5 years ago or so. These consisted of several types of media, both cheap and expensive, green and blue dye, sticker and no sticker. Basically the dye color has little effect, and stickers really do call for the early death of the media. But most of all, I think it was the early CD burning software or the actual CD-Rec drive that I used. Some earlier CD's, that I know I burned at work (using the latest software at the time) were near flawless. But a batch burned later, on a friend's computer using some lesser known software, was completely corrupt (TOC and CRC errors abound). I now make sure I get decent CDR's like TDK's (not the cheap CompUSA stuff), don't use stickers, always keep them in a multi-CD case, and run a bit-for-bit check on the archive after burning with Nero. I have yet to have a problem since I started this practice at least 2 years ago...although time will certainly tell.
  • by bigberk ( 547360 ) <bigberk@users.pc9.org> on Thursday April 22, 2004 @01:44PM (#8940918)
    I now write myself a little note on my CDRs to indicate how much of the surface causes read errors. Nero's "CD Speed" tool is very useful for this, as it has a ScanDisc tool incorporated within it.

    When too much of my CD's surface has read errors, I make a new copy of the CDR. So far I've only had to do this for 3 of my discs over the past 6 years or so.
  • use gmail? (Score:4, Funny)

    by Frederic54 ( 3788 ) on Thursday April 22, 2004 @01:46PM (#8940942) Journal
    convert everything to mp3, and send them to your gmail account, they will be kept here forever in multiple redundant copies
  • CD RW are better ??? (Score:3, Interesting)

    by iMaple ( 769378 ) on Thursday April 22, 2004 @01:47PM (#8940957)
    The article says Not all optical media is vulnerable. The rewritable variants (RW) use metallic materials that change the phase of the light, rather than light-sensitive dyes. Commercial magneto-optical and ultra-density optical systems are different too. Do they mean to say that CD RW's are resistant to aging compared to CD-Rs ??

    I always thought that CD-R s are more reliable than the RW's and genrally back up my data to CDRs ( and of course CDRW are more expensive)
  • by AtariAmarok ( 451306 ) on Thursday April 22, 2004 @01:49PM (#8940983)
    That does it. I'm converting all my mp3 collection to 8-track tapes. Does anyone know of a good 8-track tape recorder that mounts in a typical tower 5.25" drive bay to make this easy?
  • Commodore 64 Disks (Score:3, Interesting)

    by Bryan Ischo ( 893 ) * on Thursday April 22, 2004 @01:54PM (#8941054) Homepage
    On a related note, I recently recovered all of the contents off of the lone C-64 5.25 in floppy that I saved from my junior high/high school days of the late 80's. The disk had been sitting in between the pages of a programming book for around 15 years.

    I found a very nice person who had a Commodore 1571 disk drive hooked up to his PC and was able to get the files off. I was really impressed that after sitting around for 15 years, the data was all completely readable.

    I was also amazed to learn that when I was in junior high I was using a program called "SpeedScript" which I had typed in from a Compute magazine, and it had, to some degree, EMACS KEY BINDINGS!!! Holy crap, I had no idea that the emacs seed had been planted in my brain so early on ... no wonder I'm an emacs freak!
  • by rsilvergun ( 571051 ) on Thursday April 22, 2004 @01:55PM (#8941062)
    When I buy a cd in the store, I expect professional, archive quality CDs. If I've got to burn off the music myself (and can only do that a limited # of times) I've got to use my cheap 'ol cds. I guess most music services would track you're licences and let you download them again (provided you're computer hasn't changed, God I hate DRM). Still, at 99 cents/song with only shaky garuantees I can access the song perpetually, it seems like a raw deal.
  • by debest ( 471937 ) on Thursday April 22, 2004 @01:56PM (#8941075)
    Analog methods of storage (such as good old paper*) will pretty much always be able to outlast any method we have to digitally store information, at least for each "generation" of copies that are required.

    The benefit of analog is that you can store the original content for a long time, perhaps even indefinately if properly cared for. Digital, so far, seems to suffer from a lack of "permanent" media onto which content can be written.

    The big difference, however, is that with some effort it is not required to have long-life media for digital. Unlike analog content (which degrades with each generation of copy), digital content copies perfectly from one generation of media to the next. Sure, it'd be nice if you could just archive one physical copy and store it forever, but since we realistically cannot, it's pretty good that a perfect copy can be made before it degrades.

    Think of it this way: for decent preservation of analog content, you must exercise excellent dilligence in physical care; for perfect preservation of digital content, you must exercise regular, but rare dilligence in copying to a new media.

    Besides, even if a "permanent" media is created for digital content, that's no guarantee that years from now the content can even be read. What good is it for your great-grandchildren to pull out your CD-ROMs 100 years from now, and have them find that no-one has manufactured compatible devices for over 80 years, and no one has serviced one for over 50 years? That data is just as lost as it would have been if the CD had degraded.

    * Yes, I also know that today's paper is unlikely to last very long (relatively speaking), either. The papers used centuries ago withstand the aging process much better than your standard photocopier paper will.
  • by Cecil ( 37810 ) on Thursday April 22, 2004 @02:02PM (#8941158) Homepage
    ... if you know what you're doing. First of all, there are specialty CD-Rs intended for archival purposes. These will inherently last longer than normal CDs for numerous reasons, assuming the manufacturers are not full of crap. To find these CD-Rs, check a photography store, as photographers tend to have a need for both archival and mass storage thanks to digital cameras. You will likely find some there.

    Second, the biggest mistake most people make in CD archival is to write on the CDs with magic marker -- DO NOT DO THIS. The ink will, given several years, leach through the extremely thin plastic on the labelled side of the CD and pollute the optical layer, resulting in a ruined CD. Adhesive stickers, I'm told, are not much better. There are special CD-labelling markers out there, I don't know if they work well as I haven't tried them, but I doubt they're worse than a magic marker. I have found that writing very lightly with a soft, dark graphite pencil works well. If you're very paranoid, you might consider not labelling the CD at all and just be meticulous in returing it to its (properly labelled) case when you're done.

    Additionally, store the CDs properly. Somewhere reasonable. Not in direct sunlight. Safely stowed in their jewel cases.

    Of course, even doing all this, no one can tell you that your CDs will still work in 100 years. It hasn't even been 100 years since we invented the damn things, how do we know how long they will last? Still, these are steps that should allow your CDs to last for at least as long as a magnetic tape, and with perfect accuracy, as opposed to the slow degradation of audio tapes.

    What we really need is something similar to the S.M.A.R.T. technology in harddrives nowadays, to alert you that "Listen, I'm getting close to reaching the limit of my error-correction techniques here. This media probably isn't going to last a whole lot longer. You may want to do something about that." Currently, there's really no way to tell until it's too late.
    • by hankwang ( 413283 ) * on Thursday April 22, 2004 @02:17PM (#8941329) Homepage
      I have found that writing very lightly with a soft, dark graphite pencil works well.

      I wouldn't be so keen on having particles of electrically conducting graphite being spun off the disc inside the drive... But you're right that it probably won't damage the disc.

      If you're very paranoid, you might consider not labelling the CD at all

      Or write in the data-less area around the center of the disc.

    • by Rex Code ( 712912 ) <rexcode@gmail.com> on Thursday April 22, 2004 @02:41PM (#8941604)
      Second, the biggest mistake most people make in CD archival is to write on the CDs with magic marker -- DO NOT DO THIS. The ink will, given several years, leach through the extremely thin plastic on the labelled side of the CD and pollute the optical layer, resulting in a ruined CD.

      Got some studies supporting that? I did my own little study after highly doubting this rumor. Here's how I think the rumor got started:

      1. Buy cheapest Taiwanese media
      2. Write on it with a Sharpie
      3. Down the road, blame the Sharpie for media failure

      My (unscientific, but the only data point I'm aware of) test:

      In 1996, I wrote all over a Japanese Taiyo-Yuden made, unbranded Sony CD-R. In 2003, I tested the data, which was fine. I then cleaned the Sharpie ink off the disc with carburator cleaner (harsh treatment, for sure). It wiped off in seconds with no trace whatsoever, so in 7 years the ink did not migrate into the disc at all. After this, the data was still good.

      Conclusion: Buy good media and quit worrying about writing on the discs. They'll take it fine, and if they die, it wasn't the pen that killed them.
  • People are cheap (Score:5, Informative)

    by Rex Code ( 712912 ) <rexcode@gmail.com> on Thursday April 22, 2004 @02:06PM (#8941199)
    Really, what do you expect when most people pick up spindles that all some from the crappy Ritek or Princo plants in Taiwan because they can get them for $9 a spindle? I've had those go blank on my shelf too, and now I know better.

    Want a long lasting CD-R? Search the spindles to find the ones that are made in Japan. Sometimes these will be on the same shelf with the Taiwan ones, wearing the same packaging, and for the same price (if you're lucky). Usually these are made by Taiyo-Yuden, a high-quality CD-R manufacturer (and one of the co-developers of CD-R technology). Look for a frosted hub for positive ID.

    For archival quality, you'll need to spend a couple of bucks a disc on media that has a gold reflective layer. The standard here has always been Mitsui (now branded as MAM-A). Even their silver discs are a cut above in quality.

    Oh, while I'm here. In 1996 I scribbled all over a burned CD-R with various colored Sharpies, then last year cleaned it all off with carb cleaner. It hadn't migrated into the disc at all, and cleaned off without a trace. The data was fine. Anyway, I mention this because I hear people claim Sharpies kill CD-Rs all the time, and think it's nonsense. These people probably bought the cheap-o discs and are looking for something other than their own cheapness to blame it on. Oh, BTW, the scribble disc was a Sony, made by Taiyo-Yuden.
  • by zerosignal ( 222614 ) on Thursday April 22, 2004 @02:06PM (#8941200) Homepage Journal
    Many people seem to suggest reburning data every few years. But each time you do this, are you not risking corrupting a small number of files? I know OSs and hardware have error correction, but when you're dealing with gigabytes of data isn't there a risk that eventually an error will go through uncaught?
  • by The Mutant ( 167716 ) on Thursday April 22, 2004 @02:08PM (#8941221) Homepage
    One Terrabyte [lacie.com] actually, for about $1199.

    Yes, I can imagine a Beowulf cluster of these...
  • by antdude ( 79039 ) on Thursday April 22, 2004 @02:23PM (#8941396) Homepage Journal
    From Subject: [7-5] How long do CD-Rs and CD-RWs last? [cdrfaq.org]
    (2004/02/17) in CD-Recordable FAQ [cdrfaq.org]:

    CD-RWs are expected to last about 25 years under ideal conditions (i.e. you write it once and then leave it alone). Repeated rewrites will ccelerate
    this. In general, CD-RW media isn't recommended for long-term backups or archives of valuable data.

    The rest of this section applies to CD-R.

    The manufacturers claim 75 years (cyanine dye, used in "green" discs), 100 years (phthalocyanine dye, used in "gold" discs), or even 200 years
    ("advanced" phthalocyanine dye, used in "platinum" discs) once the disc has been written. The shelf life of an unrecorded disc has been estimated at
    between 5 and 10 years. There is no standard agreed-upon way to test discs for lifetime viability. Accelerated aging tests have been done, but they may not provide a meaningful analogue to real-world aging.

    Exposing the disc to excessive heat, humidity, or to direct sunlight will greatly reduce the lifetime. In general, CD-Rs are far less tolerant of environmental conditions than pressed CDs, and should be treated with greater care. The easiest way to make a CD-R unusable is to scratch the
    top surface. Find a CD-R you don't want anymore, and try to scratch the top (label side) with your fingernail, a ballpoint pen, a paper clip, and
    anything else you have handy. The results may surprise you.

    Keep them in a cool, dark, dry place, and they will probably live longer than you do (emphasis on "probably"). Some newsgroup reports have complained of discs becoming unreadable in as little as three years, but without knowing how the discs were handled and stored such anecdotes are
    useless. Try to keep a little perspective on the situation: a disc that degrades very little over 100 years is useless if it can't be read in your
    CD-ROM drive today.

    One user reported that very inexpensive CD-Rs deteriorated in a mere six weeks, despite careful storage. Some discs are better than others.

    An interesting article by Fred Langa (of http://www.langa.com/ [langa.com]) on http://www.informationweek.com/story/showArticle.j html?articleID=15800263&pgno=1 [informationweek.com]
    describes how to detect bad discs, and discusses whether putting an adhesive label on the disc causes them to fail more quickly.

    By some estimates, pressed CD-ROMs may only last for 10 to 25 years, because the aluminum reflective layer starts to corrode after a while.

    One user was told by Blaupunkt that CD-R discs shouldn't be left in car CD players, because if it gets too hot in the car the CD-R will emit a gas that can blind the laser optics. However, CD-Rs are constructed much the same way and with mostly the same materials as pressed CDs, and the temperatures required to cause such an emission from the materials that are exposed would
    melt much of the car's interior. The dye layer is sealed into the disc, and should not present any danger to drive optics even if overheated.
    Even so, leaving a CD-R in a hot car isn't good for the disc, and will probably shorten its useful life.

    See also http://www.cd-info.com/CDIC/Technology/CD-R/Media/ Longevity.html [cd-info.com],
    especially http://www.cd-info.com/CDIC/Industry/news/media-ch ronology.html [cd-info.com] about some inaccurate reporting in the news media.

    See "Do gold CD-R discs have better longevity than green discs?" on http://www.mscience.com/faq53.html [mscience.com].

  • by gillbates ( 106458 ) on Thursday April 22, 2004 @03:39PM (#8942425) Homepage Journal

    Is that I can still read data from Iomega Zip disks that are 6 years old, yet can't read CD's I burned 6 months ago. For some reason, the perils of magnetic media and Zip drives never came true for me.

    What really irks me is that CD-R was sold to the public as a way of _permanently_ archiving data. Once written, it was supposed to be permanent. The non-magnetic, non-rewritable nature of the media was supposed to prevent accidental overwrites and erasures from magnetic fields.

    Top Ten reasons to love CD-R/CD-RW:

    1. No Pesky Aborts or Retries: CD-R is the only media in which a failed write ruins the media. Retrying a failed write is so 80's. I never liked that "Abort, Retry, Ignore" stuff anyway....
    2. No Multitasking: I don't like to surf the internet or do other things when a CD is being burned. I'd rather shut down all applications, turn off my screensaver*, and watch the progress meter and wait.
    3. Home Improvement with the PC: I like having a CD coaster place setting for every chair at the dining room table. I could never ruin enough floppies for a full table's worth.
    4. Software is Never Obsolete: You never have to worry about restoring obsolete software during a system restore - by the time the software is obsolete, your CD-R backup has long been unreadable.
    5. No Pithy Operations: I hate updating single files. When I want to update an archive, I want to reburn the whole disk! (CD-R, some CD-RW here...)
    6. Snazzy Disk-Cache Progress Meter: I like disk caches. In fact, I'm not comfortable with a file transfer until I see the "flushing cache to disk" progress meter.
    7. Laid Back Attitude: I'm never in a hurry. Whether I'm just starting work or on my way out the door, I want a file transfer to take at least one minute. I would never want to save what I'm working on and immediately run out the door. (Office space, anyone?)
    8. Security: With CD-R/CD-RW, your files are always safe from editing at a public or shared computer. Even should you come across a machine with a CD-RW drive installed, the read-write latency of a CD-RW will make editing the files practically impossible. And you can forget running an application from your removable media.
    9. No Obsolete Computers: With UDF, all your friends and colleagues will have to upgrade to the latest Microsoft Operating system in order to read your disks.
    10. Prosecutorial Immunity: Should your illegal mp3 CD-R collection get seized by the police, it will be unreadable by the time it gets to trial.

    * - yes, these are the recommendations that came with a 2004 Toshiba laptop regarding making CD's.

  • Magneto Optic (Score:4, Interesting)

    by Ask-A-Nerd ( 590961 ) on Thursday April 22, 2004 @05:49PM (#8944152)
    I was one of the original developers for Magneto Optic for MaxOptics and Pinnacle Micro Systems approx 20 years ago. I still have media recorded back then on truly rewritable optical media that is 100% flawless to this day. And all this is on Plastic Media. I never did understand why magneto optic didn't catch on more. The Glass Media units I'm sure would go to 100+ years and were tested in Europe for the telephone and data companys 20 years ago, and the last I heard they still hadn't seen a single cartridge with glass media go bad.

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