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Data Storage Software

CDs, DVDs Eyed For Long-Term Archival Use 311

Posted by simoniker from the don't-lock-anyone-in-the-aging-chamber dept.
Alien54 writes "Computer scientists at the National Institute of Standards and Technology (NIST) are launching an effort to develop specifications for 'archival quality' CD and DVD media that agencies could use to ensure the procurement of sufficiently robust media for their long-term archiving needs (i.e., 50 years and longer). See the press release at the NIST site." The research involves "...enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks."
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CDs, DVDs Eyed For Long-Term Archival Use More

CDs, DVDs Eyed For Long-Term Archival Use

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  • Like having a baby (Score:5, Funny)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Thursday September 11, 2003 @05:23AM (#6928861) Journal
    Age 20 years in 3 months.

    That's what waking up at 3:00 in the morning every day to take care of the kid does to you.

  • Aging rooms? (Score:2, Funny)

    by erroneus ( 253617 )
    "...enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks."

    That makes me wonder if they are considering the use of my apartment for this...

  • CDs to use for testing (Score:4, Funny)

    by leomekenkamp ( 566309 ) on Thursday September 11, 2003 @05:25AM (#6928870)

    A link to where volunteers can submit Celine Dion, Westlife and New Kids On The Block cds to be included for testing would be greatly appreciated

  • age (Score:2, Funny)

    by selderrr ( 523988 )
    artificially age the media some 20 years in only six weeks

    that's nothing
    This [tequila-ww.com] ages braincells a solid 20 years in 6 hours !

  • The researchers are very welcome to use my workplace, it has managed to age me 30 years in as much time as their machines do (at least I feel like it).

    Might I also suggest showing the CDs and DVDs our collection of SCO stories? Those get old so very fast. They are guaranteed to feel like its been 20 years already.

  • Anyone have CDs from the 80's? (Score:4, Interesting)

    by jabbadabbadoo ( 599681 ) on Thursday September 11, 2003 @05:26AM (#6928879)
    It's almost 20 years ago since the first CD's came along.

    Are they still working?

    • Not all of them. I've heard of many reliabitity problems with old CDs, including layers of plastic splitting apart, warping of the plastic, and degregation of the reflective layer. And these are factory-pressed CDs that can barely last 20 years... I worry about my data on CD-Rs and wether or not i'll be able to read those in five years.
      • In my experience, in a batch of about 10 CDs you will be lucky not to have errors after one year. That's even keeping the CDs in the dark without use... If you use them vaguely regularly then 3 months is about typical.

        For any kind of long term storage current CD-Rs are pointless. I've since restored all my backups that I kepts and sprinkled them across hard disks and made several CD impressions, even then I know that data is going to fade away....

    • Yes I still have some CD's and a few of them are from the 80's.

      I couldn't tell you if they work or not, because all the music I play is in MP3 format.

      Why look for a 50 year solution, when in 20 years the archives will be stored on more efficient media, just like mp3's.

      • Why look for a 50 year solution, when in 20 years the archives will be stored on more efficient media, just like mp3's.

        But what are you going to store your mp3's on? CDR's? DVD-r's? Hard drives? Flash memory? We don't know much about the long-term reliability of any of those formats, although I don't feel particularly rosy about archivability prospects for any of them.

    • Re:Anyone have CDs from the 80's? (Score:5, Informative)

      by suss ( 158993 ) on Thursday September 11, 2003 @07:18AM (#6929192)
      It's almost 20 years ago since the first CD's came along.

      Are they still working?

      I have several CD's from 1985/86 that are still perfectly readable, even in secure mode with EAC (Exact Audio Copy).

      I know this because i ripped my entire CD collection (about 2000 of them) last year and very few had errors, only 1 CD was unreadable.

  • I'd settle for 10 years (Score:4, Interesting)

    by dew-genen-ny ( 617738 ) on Thursday September 11, 2003 @05:30AM (#6928889) Homepage
    Honestly,

    I've got CDs that I burned just 2 years ago, and my CD drive has trouble reading them - no scratches, it just appears that they age waaaay to quick. I know a lot of people who keep photos on CD, I hope they realise that it's not so permanent.

    Maybe something good would come of this. I'd actually be willing to pay out $5 to $10 to get a CD that once burned would stick around for a while.

    • Re:I'd settle for 10 years (Score:5, Interesting)

      by TheRaven64 ( 641858 ) on Thursday September 11, 2003 @06:34AM (#6929070) Journal
      It depends on the quality of the CD. Most of the time I use ultra-cheap no-brand CDs, since I use them for copying a few files onto to give to friends. For archiving, I have had good experiences with the Kodak Gold CDs, which have the added bonus of being a nicer than the standard vile green. They don't seem to degrade nearly as quickly. This is probably partly to do with the fact that the data layer is inside the plastic disk. With most cheap CDRs, the data layer is on top, and so can be scratched or damaged by high intensity light quite easily.

  • Know your enemies (Score:3, Funny)

    by PiscoX ( 697783 ) on Thursday September 11, 2003 @05:32AM (#6928895) Homepage
    ...enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks.
    Temperature and humidity are definitely not the worst enemies of my CDs. My friends are.

  • This is an idea, albeit not perfect (Score:5, Insightful)

    by broothal ( 186066 ) <christian@fabel.dk> on Thursday September 11, 2003 @05:32AM (#6928896) Homepage Journal
    It's cool to create media that can hold information for an extended period of time. But - do not forget that you need to have a device that can read the media. I've saved some of my earliest work from the 70's on a paper strip with holes in it, and from the 80's on a 12" floppy disk. Both look like mint condition, and I'm sure they work. But - I haven't got any hardware that can read them.

    So - if you plan to store digital information for decades, you need to store the player as well. That means, you need to make hardware that will work after, say, 100 years. This makes me think if we should strive after something that's human readable (microfilm or plain old paper) instead of something that require a computer. This is by far an easy problem to solve. My humble suggestion is to save information on todays media and prepare to copy it to a new media every 10 years.
    • I remember reading about guy who's profession was accessing legacy media. He had all this old legacy equipment which he had accumulated over the years. Companies deciding to move data over to newer media often had to contact him waving their 12" disks and tape cartridges asking for access as the old computers along with the readers had long been discarded.
    • no, you archive to then you read and rewrite to and use checksumming or similar to make sure they're ok.

      • Re:AAARgh! (Score:5, Informative)

        by RMH101 ( 636144 ) on Thursday September 11, 2003 @05:59AM (#6928979)
        damn you slashdot for removing my faux-html tags.

        What I meant to say, is:
        You write to whatever media is in vogue, and then periodically you read it back, checksum it to make sure it's not corrupted, then write it back again to a new media. Repeat ad nauseum.

        Now imagine you've got to do this for whole applications and infrastructures to support those applications, and have them instantly viewable by the FDA at any point over a 25 year period.
        This is what working in pharamceutical IS is like.

    • Re:This is an idea, albeit not perfect (Score:5, Funny)

      by selderrr ( 523988 ) on Thursday September 11, 2003 @05:56AM (#6928971) Journal
      this reminds me of a very funny story some 35 years go.

      My dad was a database guy avant-la-lettre : he used to catalogue his bibliografies and other stuff on small cards, and sort them in binders & carboard boxes all over his office.
      These cards were kinda expensive though, and ordering them on univ budget took weeks. So when computer punchards started appearing, and programmers were trowing away hundreds of cards every day after compilation errors, my dad had found is never ending source of cards. So after a year or 2, his office was littered with punchcards with text written on the back.

      Some time later, a collegue flew over from overseas for a congres. Upon seeing my dad's office and his insane collection of thousands of punchards, he went completely bananas "you've got everything on computer !! How splendid ! Could we please copy your archive to add to our own database ? "

      My dad, being a complete computer illiterate was like "duh? sure, if you think it's of any help and if you return the cards"

      So the collegue packed a few dozen boxes with cards and flew them to the US. Where they fed them into the poor mainframe....


      I still giggle when I picture the problems their IT staff must have had trying to read the damd nonsense, and the look upon my fathers face "well offcourse the data is on those cards ! Didn't you guys turn them around and look ????" :-)

  • WORMs (Score:4, Informative)

    by mousse-man ( 632412 ) on Thursday September 11, 2003 @05:33AM (#6928899) Homepage
    For this, WORM's have been invented. Currently at 9.2 GB per media, put larger versions are in the pipeline. They are still readable 10 years after, and have been guaranteed to be readable for 100 years, given the software exists.

    Just you can't burn them with your run-of-the-mill software, you need some professional software [ixos.com] for the whole document and jukebox managment as well, else you'll have some problems to find you archived data in a decade or so when the audit comes.

    • Re:WORMs (Score:3, Insightful)

      by treat ( 84622 )
      For this, WORM's have been invented. Currently at 9.2 GB per media, put larger versions are in the pipeline. They are still readable 10 years after, and have been guaranteed to be readable for 100 years, given the software exists.

      The software for HP WORM drives used on Solaris requires proprietary kernel drivers that have a license tied to the hostid of the machine. Good luck.

  • enclosed chambers (Score:3, Funny)

    by sssmashy ( 612587 ) on Thursday September 11, 2003 @05:36AM (#6928905)

    ...enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks

    Sounds like my brother's record collection just before he moved out of the basement. I could lend him a CD for a week and, if I ever saw it again, it had mysteriously accumulated a decade's worth of wear and tear.

  • Read between the lines... (Score:5, Interesting)

    by Zog The Undeniable ( 632031 ) on Thursday September 11, 2003 @05:37AM (#6928914)
    The implication is that current CD-R/DVD-R/DVD+R technology does not last as long as some people expect it to (many people archive all their digital photos to CD, for example).

    The only sure way to archive data is to keep it on a network-attached device - and migrate it regularly with changes in technology. No removable media is foolproof as hardware can break down at a time when it can't be repaired or replaced. Ask anyone with a Betamax video collection or, more relevantly, the BBC, who had great trouble [iconbar.com] reading their not-very-old Domesday archive on laserdisc. BTW, that's not a really small computer in the photo, it's a really big CD!

  • Why bother when other standards for backup media will come out that will totally put the previous generations into the obsolencense storage shed.

    How long does the magnetic bit last on a hard drive? What's all this stuff on slashdot about "Lab Diamonds" that will be used to create CPU's with insane clock speeds? Instead of DVD how about a Diamond disk of lab grown diamonds?

    Explore that!

  • 50 years is not enough (Score:5, Insightful)

    by Alain Williams ( 2972 ) <addw@phcomp.co.uk> on Thursday September 11, 2003 @05:43AM (#6928938) Homepage

    • long-term archiving needs (i.e., 50 years and longer)

    50 years is not long, 500 years is what we should be talking about.

    Books, if looked after properly, last for centuries. OK: many modern paperbacks are printed on paper that has not been properly stabilised (still contain acid), but there are plenty of very old books.

    In case you think that I am over the top: have you never looked at an old family album with pictures going back to the start of the last century? What will future generations think of us if none of that sort of material survives because we had the lack of foresight to put it onto good media?

    • 30 years is considered good enough for day to day use, nowadays. But as a teacher of mine keeps repeating: "we have more problems retrieving data from the 1970's than from the beginnig of this century" Indeed, our future generation will only see a gap...

    • Re:50 years is not enough (Score:4, Interesting)

      by battjt ( 9342 ) on Thursday September 11, 2003 @07:57AM (#6929338) Homepage
      In the big picture, who cares that a book lasts for centuries. I care that the information lasts for ever.

      Keep the data on live networked file systems and have a maintenance process.
      - When drives go bad replace them
      - Keep short term backups incase of catastrophic or human failures
      - keep hardware up to date

      The data from my file systems circa 1991 are still alive, because I continue to keep multiple copies on networks so it is easy to "rsync".

      (The 20 MB drive I was using in 1991 is dead by the way, so is the machine, its predicessor, and its predicessor. The next two are still alive, but not my primary machine. See, I have migrated my data with the technology.)

      Joe
      • On my current filesrever is my home directory.

        It was copied from my old fileserver, and the one before that.

        In there is a home dir from my Pentium 90.

        In that dir is my home dir from my 386.

        Inside that is the one from my Amiga 4000.

        Inside that is the one from my Amiga 1200.

        All the stuff I kept as text is perefctly readable.

        Xix.

    • Machine readable optical book? (Score:4, Interesting)

      by swb ( 14022 ) on Thursday September 11, 2003 @10:24AM (#6930330)
      Is there any reason you couldn't design a "book" that would actaully be a machine-readable optically scanned card deck. You'd get the advantages of a durable paper stock, and the decks could be bound in such a way that they could be mechnically unbound, read, and returned in the way similar to a tape library.

      I'm not sure what kind of data density you could get, though, although I suspect it would be slightly more than you might think. It creates a storage problem, but then it has great durability, and the machine to read it would arguably be easier to re-make in the future than the ones used to read traditional optical media, since you could include a card in each deck explaining in human terms how the deck is encoded.
  • There's a number of CDs which have already experienced 10 years of mistreatements, I wonder if any mass producing company has already learned something valuable and if they modified their production accordingly. Polycarbonate-eating fungi were already mentioned here [slashdot.org] and on Nature [nature.com] as well. Add the aluminum layer oxidation problem and my trust on cd-r as long term storage is reaching zero. I also own a couple of 10+ years old CDs (original, shush RIAA) that don't show any surface problem, but no player I hav

  • Aging? (Score:3, Funny)

    by SharpFang ( 651121 ) on Thursday September 11, 2003 @05:46AM (#6928949) Homepage Journal
    Humidity? Temperature? How lame.
    Just get the CDs to spin fast enough to make their edges reach near c speed and store the data near that edges and you're safe about aging - a year for such data will last ages for us :)
  • We just had a baby girl (yes, even geeks need to reproduce). So people ask "what can we bring the little gorgeous thing?" (they don't have to sit through nights of "woaAAAHHH!") I've figured that the best thing would be presents that she can open when she's old enough to appreciate them, like on her 18th birthday.

    DVD players may still be around in 2021, after all I can still read 3.5" floppies. But DVD media has a shelf life of 5-7 years AFAICT, several older DVDs I've tried recently don't work anymore. CDs may be less delicate, resist better.

    But if you wanted to give someone a digital present (say a bunch of their baby photos) for 18 years hence, how would you go about it?

    This was going to be an Ask Slashdot, but (a) I'm too tired, and (b) the whole "what can I give a gurgling baby" thing is not really stuff that interests geeks.
    • ...if you wanted to give someone a digital present (say a bunch of their baby photos) for 18 years hence, how would you go about it?

      Tape. Back it up onto tape. Useless as an everyday access medium, great at archiving. Also, try to keep multiple redundant copies.

      ... the whole "what can I give a gurgling baby" thing is not really stuff that interests geeks.

      Well, it interests me for similar reasons [eruvia.org]. The site you're looking at there contains photos and some smallish video. They are backed up in a copy of

      • Magnetic tapes leak, don't they? I have a pack of cassettes recorded with old stuff I wrote for a C64, 20-odd years ago, and even ten years ago they were already unreadable. This was not even high-density recording, just normal screeching. My understanding is that each layer of tape has a small effect on its neighbours, and after some time the entire tape is reprogrammed to noise. Presmably if the tapes are played and rewound the effect is less dramatic.
        But magnetic tapes do not strike me as particularl

        • Re:Does tape last? (Score:3, Interesting)

          by mccalli ( 323026 )
          Magnetic tapes leak, don't they?

          Yes. It is a pretty stable medium, but it's not perfect.

          I have a pack of cassettes recorded with old stuff I wrote for a C64, 20-odd years ago, and even ten years ago they were already unreadable.

          True, but what quality of tape? Standard C60/C90 stuff? The DV tape and format is a bit more robust than that. Also, you specifically mention the C64 - not using a D2CN are you (or was it DC2N?). They were pretty poor even with brand new tapes at a time when C64s were current

        • Re:Does tape last? (Score:3, Informative)

          by spinlocked ( 462072 )
          Magnetic tapes leak, don't they? I have a pack of cassettes recorded with old stuff I wrote for a C64, 20-odd years ago, and even ten years ago they were already unreadable.

          Not all tapes are made equal.

          Buy a couple of decent SCSI DLT drives (to best future-proof them) and a bunch of tapes. It's expensive, but they're designed to last 30+ years and will store 40gig per tape (on DLTIV), so you can store redundant copies of your important stuff on each tape.
    • Take it to your photo lab (or use your nice desktop printer :)).
      If you want to guarantee your daughter or other person can see something in 18years, create a real live touchable album.

      Providing God doesnt change the specification of human.eye() then all will be good.
      • This was also my conclusion, print out the pictures and stick them in a nice album using starch-based glue. Will be very quaint in 2021.

        But what about the videos? :-) Flip book?

        I don't really want to present my daughter with a pack of SCSI DLTs and the hardware to go. Surely something more simple... portable DVD player, maybe, complete with power supplies. If only I could be sure DVDs would last.

        Probably the best option would be a link where she can find her data online and live. Idea for a new kind

    • The longest lasting picture medium is good old B&W silver halide film, printed onto silver halide paper. You can still buy the film and develop/print it yourself in a home darkroom. If done and stored correctly, they should be good for at least 150 years. A lot of the early film pictures are still around today.

      The longest lasting color process, AFAIK, is pigment-based ink, such as the prints from an Epson 2200P inkjet printer (about $700). Printed onto archival matte paper, it should be good for about

    • I'm pretty much in the same situation as you are. I have a four month old daughter and so far I have taken 244 digital photographs of her but I often wonder about the long-term wisdom of having only digital photographs.

      Of course, as time goes by the benefits of an all digital solution will appear as well. Paper and space savings will increase as time goes by, not to mention that the money I am saving from developing photographs will pay for my digital camera fairly quickly. (When I do want I hard copy, I u

  • Durability is just one factor (Score:3, Interesting)

    by jsse ( 254124 ) on Thursday September 11, 2003 @05:53AM (#6928964) Homepage Journal
    Discs in fact are way better method of storage than traditional tape storage due to ease of accessiblity. However, in order replace tape for long term archiving, more has to be done than making durable discs.

    The other major fact is Recoverability. It's not unusual to find defective tapes before their end-of-life and we must send them to experts for retrieval of important data in them. They've technologies to recover the data, like baking the tape(yeah, bake them in oven, but please don't do it with your kitchen oven :). I do not know exactly how but they must have something to charge us enoromous amount of money for recovery. :)

    I'm not sure if existing technology could effectively recover data from aged, defective discs. That's something we must consider before they could replace traditional tape storage for long term archiving.

  • Digital Short-comings (Score:5, Interesting)

    by locarecords.com ( 601843 ) <davidNO@SPAMlocarecords.com> on Thursday September 11, 2003 @05:59AM (#6928980) Homepage Journal
    The UK Parliament not so long ago debated the benefits of storage of Government documents [the-statio...fice.co.uk] and after heated arguments decided that digital was unproven and paper itself not good enough.. especially as they want records to last 500 years.

    It shows that digital still has a long way to go compared to the current UK practice of printing on vellum... in other words goats skin !!!

    Quote: "... we compare longevity of 250 or 500 years [of long-life paper] with the 1,500 years of vellum"

    • It shows that digital still has a long way to go compared to the current UK practice of printing on vellum... in other words goats skin !!!
      In the same debate someone pointed out that the death warrant of Charles I was still available because it was written on vellum.

      He was assured that any future royal death warrants would be printed on vellum (rather than archival paper).

    • Yes, lawyers like it too. My father used to take pleasure in showing me some of the old leases and deeds he would come across which were written on vellum. The ink was basically iron oxide after so many years, and therefore still quite legible. The vellum from the late 1700s was in better condition than parchment from the 1900s.

    • Re:Digital Short-comings (Score:5, Informative)

      by njj ( 133128 ) on Thursday September 11, 2003 @08:11AM (#6929409)
      One common criticism of the use of vellum is that of animal cruelty, although it's worth noting that the goatskin used is a by-product of the leather industry, and comes from goats that had already been slaughtered to make, say, shoes.

      I was glad to hear that this latest attempt at pointless `modernisation' (for the sake of appearing `modern' rather than for any deeper and more sensible reasons) was defeated. Not least because it's really cool to be able to say ``This is actually an Act of Parliament from the 16th century, and that's actually Henry VIII's signature - not a photocopy, not a JPEG, but the real thing.''

      A related matter concerns the increasing prevalence of digital photography. As this BBC News article [bbc.co.uk] explains, digital photography may cause problems for future generations of local or family historians. Proper (printed) photographs tend to get stored away in shoeboxes in attics, and are still more-or-less as legible after a hundred years as they were when they were taken. Whereas an entire collection of digital photographs can be wiped out by one hard-disk failure.

      Or maybe in fifty years' time nobody'll know how to display a JPEG. Somewhere I've got a tape with the very first program I wrote, recorded on it. It was a simple bullseye game for the Video Genie II (a TRS80 clone) - it wasn't particularly sophisticated by general standards, but not at all bad for an eight-year-old kid. I have no means of retrieving it on any of the small menagerie of computers currently in my house.

      Another, related, example: in the mid-1980s a (for the time, pretty damned impressive) multimedia project was launched - the Domesday Project [atsf.co.uk]. This was a laserdisc containing digital reproductions of the original 11th-century Domesday Book itself (a census survey of the entirety of England ordered by William I) together with (I think) the 1981 national census data. All very innovative (albeit rather a costly system) but ironically, 15 years on, the laserdiscs are not readable by current technology - but the original 900-odd-year-old Domesday Book itself still is.

      I guess the point is that it's all very well saying ``this media is guaranteed to last for fifty years'' (although personally I'd be happier with something that'll last several hundred) but also you have to guarantee that the data format itself is going to remain readily decodeable. This is not a problem for 1000-year-old documents on vellum (as long as your Latin or Norman French is ok, and you've done a basic course in paleography).

      nicholas

  • CD's and DVDs are too small. (Score:5, Insightful)

    by Moderation abuser ( 184013 ) on Thursday September 11, 2003 @06:02AM (#6928986)
    For a start.

    A typical backup tape will handle 120Gb to 200Gb these days.

    Then you have the problem with getting hardware which will read the disks in 20 years or 50 years.

    The real solution to archiving is the ability to move to new formats as they appear and become cheaper than the existing technology, it's an ongoing process, not a product. The hardware itself should be irrelevant.

  • I appreciate this test (Score:4, Insightful)

    by Jugalator ( 259273 ) on Thursday September 11, 2003 @06:09AM (#6929006) Journal
    I understand that removable media always run a much greater risk of going bad as they're exhibited to all sorts of possibly harmful effects. However, I'd really like to see "CD-like" discs that last at least for around 20 years to give us plenty of time to at least transfer them to more modern media when they arrive. The problem right now is pretty bad since the media degrades much quicker than new technology arrives, with CD's already becoming unreadable when we haven't even fully made the switch to DVD's yet. I'm sure there are other perhaps more reliable removable media available, but they aren't as widely accepted, and I find the problem actually rather silly since reliability on removable media should come as a top priority, with those often being used exactly for storing old data not immediately needed on a hard drive -- as an archival media.

    If this test will lead to an insight in making more reliable CD's or DVD's, where those can be somehow certified with a special "Archival Quality" tag, I'm sure they would sell a lot even to a greater price. I'd completely switch to them at least, since I burn CD's to make them last for a longer time than a year or two. Switching to tapes or something like that isn't very useful, since everyone I might bring my CD's to would need a tape drive. :-P

  • This problem has already been solved (Score:5, Informative)

    by treat ( 84622 ) on Thursday September 11, 2003 @06:24AM (#6929046)
    If you're a sysadmin, this problem has already been solved. RAIDed hard drives, always on, read occasionally to check for errors, and drives replaced as they fail. Replace the drives with new models every so often (or as they fail perhaps). Replace the controller and system it is attached to as necessary.

    That is to say, that no digital storage that exists outside of a lab is suitable for long-term archival. Luckily, digital data being so easily copied (how easily people forget this!) makes this an easy problem to ignore. If you're developing new types of media, great. Otherwise, there is only one practical solution.

    Yes, "my" solution - the solution used by anyone who has digital data they want to store long-term - requires someone to babysit the data. Sorry, most things in this world need some kind of human maintenance.

    If you're storing the data on hard drives attached to a working computer, you can mirror the data on the other side of the world to protect it against any catastrophe that humans will survive.

    If you don't care about a practical solution that has by far the highest chances of success, feel free to speculate about how long CDs will last based on completely invalid lab testing. (Accelerated aging? Hah! How can they possibly account for every variable?) If you truly care about your data, keep it online and make sure someone is around to maintain the system. If you want something less, it's because you don't actually care about the data that much.

  • UV (Score:3, Informative)

    by Detritus ( 11846 ) on Thursday September 11, 2003 @06:29AM (#6929058) Homepage
    Kodak did some accelerated longevity tests on CD-Rs and found that many disks degraded rapidly when exposed to sunlight, due to the UV components of sunlight.
  • I work with video, which means that I'm generating huge amounts of data, a couple of hundred gigs of data on a busy day. As much as I'd love to archive everything, it's just cost prohibitive in both materials and time. So my solution is to seperate the wheat from the chaffe for processed data, and arhive that redundantly in both material and location, and do the same for the original source material. The idea of data corruption terrorfies me, as everything that I make is unique in the universe and could
  • Here is a project [lockss.org] based on peer-to-peer concepts that aims to preserve information over long periods of time without depending on specific media, readers, etc.

    Seems far more realistic, after all this is what most of us do with valuable data, we copy it from hard disk to hard disk over time.

  • Gold video disk with 296,000 year lifespan? (Score:5, Funny)

    by adeyadey ( 678765 ) on Thursday September 11, 2003 @06:53AM (#6929122) Journal

    In 296,000 years Voyager-2 will pass Sirius.. [nasa.gov]. Do you think the gold video disc [nasa.gov] on-board will still be readable? :-)

  • Microfilm and digital (Score:4, Informative)

    by Rxke ( 644923 ) on Thursday September 11, 2003 @06:54AM (#6929123) Homepage
    one way to preserve data longer than 50 years is still microfilm. Guaranteed to las at least 100 years, if processed and stored correctly. Currently several companies offer the service to store 'digital dots' on microfilm, instead of typeface, improving the data-density considerably. Of course density is still waaaay below that of DVD or CD, but at least you're sure it'l be there in the future, and relatively easy to read (optical-scanning...)
  • CD and DVD media have a certain lifespan. if you copy them at the end of their lifespan for archive use, will you be subject to the DCMA and can you be pursued by RIAA and MPAA? this would be interesting since the first CD's will reach the age of 20 within a few years/month...

  • My findings (Score:5, Informative)

    by Mxyzptlk ( 138505 ) on Thursday September 11, 2003 @07:06AM (#6929160) Homepage
    This is quite interesting - I'm looking into CD archiving quality right now, because I have to transfer my grandmother's story of her life from ordinary tapes to something more persistent.

    Some things I've discovered so far are:
    • The swedish national archive [www.ra.se] recommends Kodak Gold Pro for archiving purposes. However, Kodak seems to have stopped selling them...
    • Gold CDs are better than silver CDs. The worst kind of CDs are the ones that you can see right through, if you hold them to a lamp.
    • You should store your CDs in their original packaging, if available. That is: store them in a hard plastic package, and avoid soft paper or plastic. Store them upright, in 22% humidity and 5 C (66 F).
    • Avoid humidity and light as the plague - even a couple of minutes of sunlight can have a great effect. If you are really paranoid, then you should use clean cotton gloves when you are touching your CDs. Of course, scratches, finger prints as such are not good...
    • You should use CDs with less storage space, because the bigger the room each bit has, the less risk is it that that bit can be destroyed.
    • If you must write something on the CD, then write as near the center hole as possible, and use you smallest handwriting. The color of the pen can actually affect the reading capability of the data, although the data is on the opposite side of your text.

    The biggest problems seems to be that the CDs come and go, so it can be difficult to get the tested products. The tests that has been done has used "accelerated aging", which is just a simulation. That is, there is no real experience in aging CDs.

    My advice would be to store valuable information on as many different formats as possible. Continually monitor the quality of these, and transfer to new backups when they start to degrade too much.

    Hope this helps!
    • The MAM-E (former Mitsui) Gold Archive and Verbatim Datalife Plus are the best CD/DVD blanks you can get in terms of longevity. In general, these brands along with TDK are what I recommend to folks almost exclusively because they have the best quality control. I've heard good things about Taiyo-Yuden and Mitsubishi's high-end blanks as well. Sadly, Kodak Gold blanks are no longer made, but if you can find some, go nuts on them.

      Longevity is the last thing that people are thinking about. That's why cra

  • Vinyl records don't evaporate. (Score:5, Interesting)

    by crovira ( 10242 ) on Thursday September 11, 2003 @07:08AM (#6929168) Homepage
    And acid free paper doesn't turn to ash.

    The RIAA must be ROTFLTAO at the thought that the plastic they sell is a perishable good. Only slightly (take the long view, some books are hundreds of years old,) more perishable that the original source which only lasts as long as an echo.

    I have vinyl from the '60s and '70s that I played on a good turntable then and (since I still have that turn table,) I can still listen to now.

    Since the early 20th century, our industrial processes have been destroying our heritage.

  • Grim stuff. (Score:2, Interesting)

    by cwsulliv ( 522390 ) *
    Considering the relatively short life expectancy of digital media, the DMCA, and the extensions to copyright term over the past few decades, imagine the Dark Age our children and grandchildren will be facing 50-100 years from now. Only the memories of old men and women and the loot of "pirates" will be available to help fill in the great blank space in our cultural history.

  • Copying from generation to generation doesn't cut (Score:5, Insightful)

    by OzPeter ( 195038 ) on Thursday September 11, 2003 @07:43AM (#6929270)
    I see a lot of people saying that the short CD lifespan is not a problem .. you just copy from one generation of media to the next as you approach the optimum time.

    Well that doesn't really cut it for two main reasons

    1/ You have now decided that the only information you will hand down to the future is that the stuff that you care about now. As soon as you stop caring about that data, or your descendants stop caring, then that data will lost.

    2/ It will only need a skip of roughly 2 generations of technology before you won't be able to recover any digital data that you (or someone else) accidently re-discovers.

    If this doesn't seem important, look at what historians and archeologists are finding/learning from poking around things that have survived millenia, compared with the despair of knowing what huge gaps exists from records/items that have been irretrievably lost.

    So how do you want to judge the concept of "archival"? As something that is accessible as long as the item is whole, or as something that requires active intervention to maintain its integrity?

  • Technically possible, yes. Economically, maybe. (Score:4, Informative)

    by shoppa ( 464619 ) on Thursday September 11, 2003 @07:57AM (#6929337)
    We have had very good archival quality CD's already. For example, Kodak Gold and Mitsui Gold. Both manufacturers published extensive technical documents about accelerated age testing under extreme conditions, and the results indicated lifetimes greater than 100 years in normal or good storage conditions. The reflective surface was real gold, the dye used was the "good one" (phthalocyanine), and there was a decent top layer over the reflective surface (IMHO Kodak was the clear winner here).

    The difficulty is that these disks cost a dollar or two each. Compare this with the el-cheapo ones that sell by the billions. Few mass consumers bought the good CD's, and Kodak stopped making them entirely and the Mitsui's are now specialty products that are not widely available.

    There's also been a major shift in where and how CD-R's are manufactured. At first they were high-spec products, made in a few select factories in the US and Japan. Then manufacturing scaled up and cheaped out as the plants moved to Taiwan. Now a lot of those plants are going even lower-budget and moving to Mexico and mainland China.

    The point is that consumers rarely buy for longevity... they go for neat packaging or cheap price or high burn speed or something else. The CD manufacturers have learned that lesson well. That's why it's so hard to buy good archival CD-R's anymore.

  • Obligatory Virgil quote (Score:5, Informative)

    by panurge ( 573432 ) on Thursday September 11, 2003 @07:58AM (#6929342)
    "Monumentum exigere aere perennius" - "I have created a monument more durable than bronze". Virgil meant that he knew his words were worth preserving, and so people would find a way to preserve them. And in general, that's it. Things worth keeping get endlessly copied and stay in circulation. No matter how durable the material, no matter how human readable, if the language is lost the meaning is lost. Etruscan is unreadable, Latin is readable because the Romans built the great civilisation and the Etruscans didn't. Great paintings survive because they get cleaned, restored and generally looked after.

    But CDs are an interesting case. You could argue that, unless we lapse into complete barbarism or some rejection of science, recovering old CDs should be possible for any future civilisation if the bit pattern is preserved. Provided the encoding and protocols are stored safely somewhere, it should be possible to construct a reader if anything is considered important enough to read. Unlike tape or punch card, the mechanical handling needed for a CD reader is very simple. Small lasers are made in ever greater volumes, and anything that replaces them is going to be more, not less capable. They use little power and there is no environmental reason why they are likely to fall into disuse.

    Even so, my best photos are printed on archival grade non-resin coated acid free stock that should last a couple of hundred years. As if anyone is likely to care.

  • Film is better than CD's (Score:4, Informative)

    by rockhome ( 97505 ) on Thursday September 11, 2003 @08:02AM (#6929367) Journal
    Why not archive on a high-quality film?

    If documents are important to archive, especially for long periods of time, transferring the data to a less technical medium such as film is a much better alternative to the CD.

    20 years ago, a great many people owned 8-Track tapes and players, along with record albums on vinyl. Very few of these items are readily available. I certainly know a few people with turn tables, but no one who owns an 8-Track player.

    Whos is going to gurantee that the technology in use in 2103 can read a CD created in 2003? By storing data on film, even as a series of light/dark bits, requires very little technology for retrieval. Think about that, a lamp, a lense, and a wall to view an image. Data encoded as a string of bits could easily be read into a recording device.

    Many types of film can be stored for much longe periods than CD's, and can be easily copied and in some cases restored.

    Why does no one take a Tyrant like approach to this problem?

  • One solution - less density (Score:5, Insightful)

    by joshv ( 13017 ) on Thursday September 11, 2003 @08:07AM (#6929381)
    Many people have talked about older methods of storage as the gold standard. Paper, vellum, papryrus, clay tablets - some documents written on these media have survived thousands of years.

    BUT, they have not survived that amount of time without degradation. The reason we can still read them is because of their low information density. Documents can fade - a 1 inch square portion of a document could flake away, leaving the original text still readable. Why? Because 1 square inch of most documents doesn't contain all that much information.

    As physical objects I suspect that quality CDs or DVDs would degrade less over 1000 years than just about any of the other media I've previously mentionned. The problem is that we are trying to cram so much data onto them that even the slightest bit of degradation leads to data loss.

    So what's the answer? Massive redundancy. Replicate data in 100 different ways across the surfaces of the CD or DVD - this might dramatically decrease the storage capacity, but even 10 MB on the surface area of a CD is a massive improvement over the storage density of vellum. Now you have a chance of lasting 1000 years. Even if the CD is shattered and all some future archeologist can find is a shard, there is a good chance that the entire data set is contained within that shard, perhaps even multiple copies.

    Even further, one could imagine using file formats that are resistant to file errors, perhaps uncompressed raster images. Easy for future scientists to decode, and wonderfully resistant to degradation. This is just another way to decrease density.

    -josh

    • So what's the answer? Massive redundancy. Replicate data in 100 different ways across the surfaces of the CD or DVD

      I think you are really heading in the wrong direction with this. Instead of expecting everything to be destroyed by the elements, and adding in more redundancy to (do a poor job) compensate, you just need to make the housing material much more durable, so it can sheild the data from damage.

      Stick a few DVDs in a thouroughly padded steel case, then drop it down a mountain, and you won't see a

  • Accelerated aging (Score:4, Interesting)

    by winkydink ( 650484 ) * <sv.dude@gmail.com> on Thursday September 11, 2003 @08:32AM (#6929510) Homepage Journal
    enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks

    Wow! I wonder if I can get one of these for my wine cellar.

  • ...that the commercial products actually meet the government specs?

    We are already in a situation where every CD-R vendor claims to meet the industry specs, and every CD-R drive claims to meet the industry specs, yet it is not rare at all to find drives that like some brands of CD-R but not others.

    It's not just a question of "using name brands" or "avoiding bargain brands," either.

    When people raise this issue in e.g. comp.publish.cdrom.hardware, the answer is always "do your own media tests," and when som

    • What we really need is for CDR drives to have a nice, continuous,
      real-time indicator that measures signal strength, or quality, or
      something like that... something that would give that a disk, while still readable, was starting to fade.

      I believe cd and dvd drives already have that at the scsi command set level. It just needs software to display the info.

  • Mr. Anderson! (Score:3, Interesting)

    by Trolling4Dollars ( 627073 ) on Thursday September 11, 2003 @09:00AM (#6929667) Journal
    What good is archival quality media, if you don't have the device to read it with?

  • A simple plan (Score:2, Informative)

    by Boiner ( 58993 )
    My simple plan is that each off-site CD (tape) that I make gets a date. I keep 5 year's worth of data.



    Once I accumulated 5 years worth of backups, I copy the expiring data to new media and throw the old away, this gives me a little protection from 1) aging media and 2) aging i/o devices. I also make sure that as I get rid of older devices, that I convert all backups it might use before getting rid of the device.



    Simple, but it works well for me.

  • Good idea; data decay rate on CDRs is surprising (Score:5, Interesting)

    by bigberk ( 547360 ) <bigberk@users.pc9.org> on Thursday September 11, 2003 @09:30AM (#6929868)
    When I read the previous slashdot post about CDRs rapidly decaying (even becoming unreadable in a few years) I had trouble believing this... but I ran my own tests using the "Nero CD Speed" tool's ScanDisc option.

    What I found was that my 3 to 4 year old archival CDs had anywhere between 20% to 50% of their surface damaged; they had (recoverable) errors. This spanned multiple brands, including Memorex, Acer, and HP.

    Remember that data correction algorithms can recover from minor errors, but if data is becoming damaged this quickly it will be not too long before data is actually lost on CDRs.
  • Stone tablets last thousands of years, and it's off the shelf technology.

  • Solution already exists for serious archiving (Score:4, Informative)

    by h4mmer5tein ( 589994 ) on Thursday September 11, 2003 @09:58AM (#6930104)
    The problem :

    A paper based collection of 100,000+ maps dating back to 1886 that are slowly decaying with use. They require digitisation for long term ( 200 years +, at least as long again as they have survived already ) archiving but need to be available quickly and easily for viewing on demand. Total storage requirement is in excess of 150 Tb.

    The Solution :

    An archiving setup using Magneto Optical technology in managed jukeboxes in a controlled environment. MO has been around for nearly 20 years now and is a highly refined and proven technology. Current capacities are up to 9.1 Gb per media item with 30Gb coming online in the near future. Jukeboxes handling up to 10Tb per unit are readily available now.

    MO doesnt use dye at all. The laser melts a magnetic substrate that is then manipulated by the write head to impart the data in a similar way to a conventional disk, the sustrate cools and the data is permanantly stored. There is no degradation of the media by sunlight, heat etc as compared to DVD or CD formats. It's more accessable and requires less management than tape, its cheaper than conventional disk, off site storage of duplicate media is easily achieved, data throughputs are faster then DVD or CD and capacity is as good or better than either.

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