Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
The Internet Data Storage Media

Most Digital Content Not Stable 353

Posted by Zonk from the define-stable dept.
brunes69 writes "The CBC is running an article profiling the problems with archiving digital data in New Brunswick's provincial archives. Quote from the story: 'I've had audio tape come into the archives, for example, that had been submerged in water in floods and the tape was so swollen it went off the reel, and yet we were able to recover that. We were able to take that off and dry it out and play it back. If a CD had one-tenth of one per cent of the damage on one of those reels, it wouldn't play, period. The whole thing would be corrupted'. Given the difficulties with preserving digital data, is it really the medium we should be using for archival purposes?"
This discussion has been archived. No new comments can be posted.

Most Digital Content Not Stable More

Most Digital Content Not Stable

Comments Filter:

  • That's nothing, think of DRM (Score:5, Insightful)

    by iamacat ( 583406 ) on Tuesday March 20, 2007 @11:57AM (#18416771)
    That content can not be preserved at all. We'll be a civilization without written history, like American Indians.

    • Re:That's nothing, think of DRM (Score:5, Funny)

      by Rude Turnip ( 49495 ) <valuationNO@SPAMgmail.com> on Tuesday March 20, 2007 @12:08PM (#18416987)
      And if they didn't insist on DRM in their smoke signals, they might still be a pretty formidable group today.

    • Re: (Score:3, Funny)

      by dr.badass ( 25287 )
      That's nothing, think of DRM. That content can not be preserved at all.

      That might mean something if DRM magically retroactively destroyed all non-DRM copies of the content it contains. Like, say, the original.

      Ten years ago my VCR ate my copy of Citizen Kane, which might have been a cultural tragedy, but fortunately someone had the foresight to give me a copy on VHS instead of the original print.

  • Multiple identical copies? (Score:5, Insightful)

    by WinterSolstice ( 223271 ) on Tuesday March 20, 2007 @11:57AM (#18416781)
    Isn't that the point of digital? Lossless copies are possible (depending on format obviously). Why have one plastic cylinder that can be lost when you can have it in 5 or 10 locations?

    • Re:Multiple identical copies? (Score:5, Informative)

      by t00le ( 136364 ) on Tuesday March 20, 2007 @12:02PM (#18416877)
      Any good backup strategy will have multiple media types, so CD/DVD should not be your primary backup media type. If you prefer to have an medium for fast access, then it is still viable. As long as it is not your primary media type, which should be something with tried-and-true longevity.

      • The point is: Like what?

        • Re: (Score:2, Informative)

          by t00le ( 136364 )
          Hrmm,

          DLT
          reel-to-reel
          Mini8mm
          SAN
          CD/DVD
          etc...

          Depends on how deep your pockets go and your calculation for the value of the data if lost. You are doing the math on loss of data, riggghhhhttt?

      • Re: (Score:3, Funny)

        by sporkmonger ( 922923 )
        We know papyrus has tried-and-true longevity for sure. Everything else is just a pretty good guess.

    • Re: (Score:2)

      by Vokkyt ( 739289 )
      Exactly; granted, you can kill a DVD, a HD, or a CD relatively easily; however, at the same time, you can archive to all three in a few minutes, whereas making carbon copies of film strips and audio reels takes considerably longer and also is not as easily stored as digital content. On top of that, access becomes an issue; watching 8mm films requires a projector to display them, meaning you have to keep a projector in good working condition while parts and service-workers for the projector vanish as new te
      • All of which indicates that digital is not a preferable mechanism for recording, but only for working copies and transmission. The very process of converting from analog to digital automatically results in tremendous data loss the moment you do it when you get right down to it.

        • Re: (Score:3, Insightful)

          by twistedsymphony ( 956982 )

          All of which indicates that digital is not a preferable mechanism for recording, but only for working copies and transmission. The very process of converting from analog to digital automatically results in tremendous data loss the moment you do it when you get right down to it.

          You're assuming the source is analog... what about material that is no different in digital then in analog... if I write a book, or an application, what if the source is a picture, video or audio but one that was originally created o

      • Re: (Score:3, Insightful)

        by Hoi Polloi ( 522990 )
        You assume though that the digital format you've chosen will be readable decades later. The details of the encoding method may be forgotten or even hidden behind DRM laws and the physical means of reading them may be lost as the technology changed. How many 5.25" floppy drives do you still see? I think NASA has faced this issue with old Apollo data fom the 60s.

      • Re:Multiple identical copies? (Score:4, Funny)

        by eno2001 ( 527078 ) on Tuesday March 20, 2007 @12:39PM (#18417533) Homepage Journal
        Digital media is OK, it's the storage that sucks. That's your basic point. But I have to disagree with you on the ubiquity of CD-ROM and DVD-ROM drives. Trust me... of all those devices that exist today, you'll only find less than 1% in a serviceable state in another 75 years. What we really need is a self-replicating storage system that builds copies of itself. I propose that for proper storage of digital information, we should really be looking at systems that can store the data in a sequential chemical form (to represent the bits). These systems should be very compact and only contain a limited set of data + the ability to copy that data to neighboring units. (Death by a thousand paper cuts sort of thing) These small systems would be contained within larger systems whose sole responsibility would be acquiring the necessary physical resources (complex matter that could be broken down into the base chemicals needed by the smaller storage systems).

        The larger systems could also provide mirroring by interfacing with each other as directed by chemical interactions in order to preserve original data as well as integrate new data that may be useful in assuring that future units are even more resilient to any sorts of flaws or possible malfunction caused by inappropriate chemical input. The key to all of this is going to be to make sure that the larger units are impelled to continue the duplication and exchange of data ad infinitum. To do that, there should be some sort of mutual benefit that the engaged units acquire from the mirroring. Multiple levels of mutual benefit would likely be more successful than just one level. So I propose that at a base level, the units should be programmed with routines that make them feel more or less successful whenever a mirroring connection is attempted. I know that sounds strange, but it should be a pretty simple subroutine and will at least get the units to attempt mirroring.

        The next level would also be an expansion of the data mirroring to the actual manufacture of a tertiary (or even more) unit that contains selected data from both origination units. As part of the mutual benefit relationship between units, the origination units should be programmed to protect the manufactured unit in order to safeguard its data as it would be the freshest copy (chemically speaking) and therefore more viable. So the relationship between origination units and next generation manufactured units would be that of security and stability from the origination units as applied to the next generation.

        Another aspect to all of this that would add even more value would be to provide the larger units with various sensors that would store ANY and ALL possible forms of energy radiation and chemical exposure to the environment. This would assure that the units would not only contain the originally stored data, but would be constantly gathering the data in a parallel fashion in every corner of the world where the units are deployed.

        As you can see, this would ensure after several generations, that all the original data is in tact and could simply be retrieved by reading all units chemical stores simultaneously and reassembling the original data as well as newly stored information. Imagine that... a sensor array that spans the planet with historical functions as well. And all self-sustaining and chemically based.

    • Every Superman has his Kryptonite (Score:5, Insightful)

      by elrous0 ( 869638 ) * on Tuesday March 20, 2007 @12:07PM (#18416969)
      Yes, analog tape is durable. But let's take it and that "CD" and put them in front of a large electromagnet and see how each fares.
      • Unless of course you let the face of the cd hit the piece of metal. then it gets scratched.
        • If the data on the CD is particularly valuable, the face of the CD can be polished to remove the scratches, as long as they're not too deep. There's commercial machines which do this, and there's online services that you can send your CDs to to have this done at a reasonable price (less than the cost of a music CD each).

    • Precisely (Score:3, Insightful)

      by Sycraft-fu ( 314770 )
      I don't know what it is with /. but it seems this kind of infopocalypse story comes up at least once every 6 months in regards to digital data. I can only think one thing in each case: This is fucking retarded.

      As you said, the great thing about digital data is that is can be replaced cheaply, perfectly, and spread around. It's resilience isn't in the one copy lasting 1000 years, it is in having copies everywhere, so no even short of nuclear war can eliminate them all, and maybe not even then.

      This also is th

      • This also is the response to the other big cry-wolf thing, "What happens when the data is in a format that's too old???!!11one" The answer is we just keep copying it to new formats.

        It's a stupid fucking argument anyway. I think I am not alone when I say that, for example, I have a C= 1541 lying around. That's an old-ass format, but there's probably tens of thousands of them sprinkled around through geeks' bedrooms alone.

        Hobbyists alone are sufficient to maintain the means to read old data formats, and som

      • Thanks for summing this up perfectly - if you care enough to get it, it's possible.

        I lost a lot of my childhood stuff (since stuff like Splash doesn't even have a reader for the format anymore), but if I cared enough I would have deliberately saved it. Just like I could save my children's "fridge art".

        Archival quality data is easily saved if you care. (DRM or not)

      • Re: (Score:2, Interesting)

        by skoaldipper ( 752281 )
        Here's [computerworld.com] an alternate article which might shed some light:

        "Unlike pressed original CDs, burned CDs have a relatively short life span of between two to five years, depending on the quality of the CD,"[...]The problem with hard drives, he said, is not so much the disk itself as it is the disk bearing, which has a positioning function similar to a ball bearing.[...]Gerecke (a physicist and storage expert at IBM Deutschland GmbH) suggests using magnetic tapes, which, he claims, can have a life span of 30 to 100 y

      • This also is the response to the other big cry-wolf thing, "What happens when the data is in a format that's too old???!!11one" The answer is we just keep copying it to new formats. I have digital copies of papers that I wrote in high school. They were written on an old copy or Works for Windows 3.1 and usually saved to floppy. I don't have a floppy any more but it isn't a problem. I long ago transferred them to a harddrive and I just keep transferring them to new drives when I get them. I also periodically load the old documents in to whatever my current word processor is, convert them, and re-save them as a new format.

        I think you're missing an important element here. As you move along in time, the volume of data that must be converted to the format du jour only gets bigger and bigger.

        For a single person, it's probably not too bad. I, too, have pretty much everything I ever wrote since I first got a computer, and every few years I've committed to rolling the whole thing onto new media. So I've gone from offline backups on floppies, to Zip disks (in retrospect a mistake), to CDs, to DVD-R, and now to DVD+R (the -R discs were crappy and I've since heard that +R is a superior format anyway). This isn't much trouble, because the amount of data I have to backup hasn't really grown that much faster than the data density of available media. I'm probably up to a couple of DVDs for the stuff I really, really care about, maybe a binder if I include all the photos and video.

        But what's a basic Saturday-afternoon copy-and-burn job for an individual is a Sisyphean task for a large government agency or library, particularly one who is constantly generating new content. I've seen places that could barely keep up with archiving the stuff they were producing, much less roll their vast archives forward onto new media. So they'd have vaults of hard drives, sitting next to DLT cassettes, next to IBM 3480, next to racks of old half-inch open-reel tapes. Probably back in some dark corner there were piles of punched cards; it really wouldn't surprise me. The problem of data loss due to unreadable formats isn't some abstract 'maybe,' it's already happened in a lot of places (but nobody really wants to talk about it, so it mostly gets buried and whatever's on the tapes gets written off).

        The reason why there's so much interest in preservable formats is because while it may not be strictly impossible to constantly roll old backups and archives forward, it's very hard, and requires vast amounts of effort and expense. If you have a backup that's being written into a format that you know is going to be readable for a long time, even if it's more expensive to write initially, you can save a lot of money and time down the road by not having to copy it forward as often.

        People may get a little shrill when they're talking about these issues, but they're quite real.

        • Re: (Score:3, Interesting)

          by dhasenan ( 758719 )
          So don't convert the content to the new format -- port the viewer / player / codec. Then if the new formats are that much better (or simply more common), convert to the new one whenever you play back anything in the old format. That'd be much cheaper on computation and disk transfers (or at least it would deamortize them), though it might incur additional lag in playback.

      • and re-save them as a new format.

        I've got maybe 400 DVD's full of stuff here. If you think I'm copy that lot to Blu-ray or whatever, you've got another thing coming. I got to a point a couple of years ago where I decided I'd only stick stuff on DVD by making 2 copies on 2 different brands & keeping them in a dark cupboard. I also only bothered backing up stuff that I wouldn't be *that* upset if I lost. The really important stuff is mirrored over 3 hard drives so if one dies, I have 2 copies to create

    • Re:Multiple identical copies? (Score:5, Insightful)

      by gad_zuki! ( 70830 ) on Tuesday March 20, 2007 @12:19PM (#18417187)
      The cost of multiple backups is very real. The real issue here is that this is a frivolous complaint. First off, wet tape being readable is an artifact of the medium. The rosetta stone in the british museum is pretty readable but we arent exactly throwing out our modern media to go back to stone. Also, lets consider a reel to reel tape is about 90 minutes (7inch). 650 megabytes on a standard disc at encoding similiar to the quality you get out of a reel to reel tape is something like 1,500 minutes. And its smaller. So lets not go a little too crazy with idealizing the past.

      Also I'm certain for every analog horror story there is a digital lucky story (and vice versa). Not to mention digital encodings usually have some kind of redundancy. A small scrach does nothing but the same scratch on an lp forever destroys some part of the track. I wont even go into the magic of data restoration (which the author ignores). There's really no 'tough medium for the ages' out there that can do it all. Just complaints and blind-luck stories.
    • Yep. Librarians and archivists aren't stupid -- that's why we have invented digital replication systems like Lots of Copies Keep Stuff Safe [lockss.org]. From the site:

      Libraries are using the LOCKSS Program to build libraries! With publishers, our community is working to retain libraries as long-term memory organizations in the electronic environment.

      People with responsibility for scholarly assets agree: digital preservation is important. With your help, librarians and publishers are asking two fundamental questions:

    • This is a good point. If we had to rely on actual archives from the classical period, we'd have very little of the period's writings. Almost everything we have from antiquity comes from Monks who copied the stuff. Of course, they were human and susceptible to editing now and then. Digital copying as an archive format works only if it's massively redundant, but if that's the case, it's better than having a single stone etching of all your data. Easier to store in the closet, too.

    • Re: (Score:3, Funny)

      by Not_Wiggins ( 686627 )
      Exactly! Why store it on plastic at all?

      What I do is take files I care about, encrypt them, rename the file to something tempting like "Cheerleader Sex Orgy XXXIV.avi," note the MD5 (sticky note on the next of the monitor), and share it on a P2P network.

      Instant distributed backup! 8D

      • Re: (Score:3, Funny)

        by WinterSolstice ( 223271 )
        "Only wimps use tape backup: _real_ men just upload their important stuff on ftp, and let the rest of the world mirror it " --- Linus Torvalds
    • I think what the original poster meant to say was, "With digital you either get a perfect copy, or a corrupt copy. With analog you always get a corrupt copy."

      Digital content isn't unstable, it's just more sensitive to corruption because in general software expects to be able to extract a perfect copy every time, rather than a near-perfect copy. Whether you can recover partially corrupted digital data depends on several things:

      A) Choice of filesystem (journaling, error correction, built-in redundancy)
      B) Choi

  • Stone tablets (Score:5, Funny)

    by IckySplat ( 218140 ) on Tuesday March 20, 2007 @11:58AM (#18416785)
    Stone tablets. Just drill a hole for a zero and your away and laughing
    Now we just need a large enough area to store them :)

    • Stone tablets. Just drill a hole for a zero and your away and laughing
      And make a scratch for an apostrophe and e!
    • Actually, you are not far off. You need one of these: http://en.wikipedia.org/wiki/Rosetta_Project [wikipedia.org]
    • Hey, it worked for Moses...the 10 commandments are still around.

    • Re: (Score:3, Insightful)

      by NewWorldDan ( 899800 )
      Rather glib, but a very important point. The biggest problem is data density. The higher the data density, the less damage it takes to destroy it. The other upside to digital data is the ability to build in fault tolerance. CDs, for example, are fault tolerant. They can accomodate a certain number of scratches and bad blocks and still produce 100% accurate output. On the other hand, this tolerance comes at the expense of (wait for it) data density. The upside to analog data, is that damage distorts w
    • Og drill many zero. Stone fall apart. Maybe Og need invent sparse file storage.

    • This is a dual problem:

      1) Digital data needs to be moved about once every 5 years onto a new physical store, disk, whatever. Think of the amount of data sitting around on floppy disks that is being lost as we speak.

      2) Data has to be recorded in a way that that presumes whatever software you use to create it will not exist in the future. Anyone who saved their life's work in some ancient binary word processor file will know what I mean. For most computer-based data storage that requires data be stored s

  • oh, just (Score:3, Interesting)

    by superwiz ( 655733 ) on Tuesday March 20, 2007 @12:00PM (#18416817) Journal
    let's play it all by memory. Seriosly, do we really have a choice? The more densely we pack the information that more of a chance it has for corruption. The "CD" mentioned by the article has effectively 700 minutes of music of the same quality as the 60 minute tape.
  • I like that digital content is fluid and can be easily changed.

    The real problem is more that the media is not stable. Optical disks are certainly not a long term archival strategy.

    I wonder if there's a good way to convert digital video into black and white film (maybe with one frame per color channel) since it's got a proven archival record.

    • Re: (Score:2)

      by AJWM ( 19027 )
      I wonder if there's a good way to convert digital video into black and white film (maybe with one frame per color channel) since it's got a proven archival record.

      As long as you're not using nitrate based (celluloid) film stock -- a lot of pre-1950s footage has disintegrated. For that matter even acetate-based stocks tend to deteriorate over time.

      There are other film types -- and the stuff they use (used to use?) for microfiche is rated in centuries if kept in climate-controlled conditions. Under hot and

  • 3.5" (Score:5, Funny)

    by otacon ( 445694 ) on Tuesday March 20, 2007 @12:00PM (#18416825)
    At the enterprise level we use 3.5" 1.44MB Floppy drives in an elaborate redundant array. It consists of roughly 70,000 Disks, each changed nightly. We haven't had any problems yet. Hopefully the rest of the world will play catch up soon.

  • It's the messanger, not the message (Score:4, Insightful)

    by Anonymous Coward on Tuesday March 20, 2007 @12:00PM (#18416827)
    Ridiculous. It's not the fact that content is digital, it's the fact that the media being used to store the information (CDs etc) is fragile. If these mythical audio tapes had been digital tapes, recovering the signal from them would have been just as easy.

    • Re: (Score:3, Insightful)

      by realmolo ( 574068 )
      But it *is* that the content is digital.

      Those audio tapes were "recoverable", but I bet they didn't sound all that great. Good enough to be understood, but nowhere near the original quality. An analog signal that is "garbled" is still usable.

      If there had been *digital* data on those tapes, then it's pretty likely that enough of the data had been corrupted that the files would have been *unusable*. Once the bits are gone, they're gone. Throw in the fact that there no guaranteed that the encoding and file for

  • But what you got off the tape... (Score:5, Insightful)

    by dave420 ( 699308 ) on Tuesday March 20, 2007 @12:00PM (#18416839)
    ... wasn't *exactly* what you put on. You have the appearance of stability, that you can retrieve something off a damaged tape, but the truth is something different. That's the beauty of analogue. The same simplicity and fault-tolerance of the format also means the format will naturally degrade over time. The contents may be retrievable, but they've degraded, and as such are not the same contents as when first written. Digital fails, but when it doesn't fail, you have exactly the same content as you did when you started. Archivists will not run from digital - their techniques will improve instead. or something.
    • Audio recordings, especially voice recordings, are so full of redundancies that you could lose up to half of the recording, and still have recoverable audio. If you had that redundancy spread over several CDs (something RAIDlike) you could recover your data.

  • First (Score:3, Interesting)

    by WormholeFiend ( 674934 ) on Tuesday March 20, 2007 @12:00PM (#18416841)
    we need to realise that nothing lasts forever.

    Then, we can figure out the most cost-effective medium to record stuff on, with determined re-archival cycles.

    • Re: (Score:2)

      by VE3MTM ( 635378 )
      we need to realise that nothing lasts forever

      Tell that to the Egyptians, the Romans, or any other ancient civilization. Many of their creations still exist today. Can the same be said for ours?

  • Crush and Preserve! (Score:4, Funny)

    by webword ( 82711 ) on Tuesday March 20, 2007 @12:02PM (#18416871) Homepage
    Shouldn't it be possible to take all the media and just crush it? You know, like throw it into a Mega Power 3000 Digital Garbage Collector (TM) and crush it into a diamond or something? Let future generations figure out how to decompress it.

  • wring recovery method (Score:5, Informative)

    by Red Flayer ( 890720 ) on Tuesday March 20, 2007 @12:04PM (#18416905) Journal

    If a CD had one-tenth of one per cent of the damage on one of those reels, it wouldn't play, period.
    That's because you're trying to optically read through the damaged part. It is possible to recover data from damaged discs, as long as only the coating (and not the reflective surface) is damaged. It is quite possible to polish the surface and read the data, or even to fill in some of the damage and repolish for reading.

    Just because it's harder to recover the data doesn't mean it's impossible.

    Of course, anyone using CDs or DVDs for large data backup must have a lot of interns to do the disc swapping.

    • Re:wring recovery method (Score:5, Informative)

      by Criffer ( 842645 ) on Tuesday March 20, 2007 @12:16PM (#18417129)
      Exactly. If you try to put a bent CD into a CD drive, you're obviously not going to be able to read it. But that doesn't mean its not recoverable.

      To recover data from a CD, you can simply photograph it at high enough resolution. Even with huge scratches, even with parts of the disc physically missing, you can recover the data exactly as it was encoded. How? Reed Solomon code [wikipedia.org] .
      Quoth wikipedia:

      The result is a CIRC that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface. This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts
      • Reed-Soloman is designed to correct for error bursts - eg. scratches. That's why it is ideal for CDs and DVDs.

        But it can not compensate well at all for even medium amounts of random bit errors. These are the exact kinds of errors that occur on CD and DVD media over time as it degrades. That is what is being referred to here.

        If you have a piece of analogue data, and it degrades, you can still get enough meaning from the original to make it worth archiving. A piece of digital data with even a relatively small

  • They could try harder (Score:4, Interesting)

    by Waffle Iron ( 339739 ) on Tuesday March 20, 2007 @12:04PM (#18416913)
    The CD wouldn't play with an off-the-shelf CD player. That doesn't mean that a special "archaeological" CD player can't be built that would perform extensive microscopic image analysis of the disk surface in order to read the data in the face of extensive corruption.

    Some analog technologies, like old color films, have also degraded and need image enhancement to recover the original content.

    • Re: (Score:3, Informative)

      by clickclickdrone ( 964164 )

      a special "archaeological" CD player
      I believe they exist already - just as there exist devices for reading fragments of shattered hard drives. Forensic data recovery experts have some pretty funky kit at their disposal.

  • have people already forgotten? (Score:5, Informative)

    by phantomfive ( 622387 ) on Tuesday March 20, 2007 @12:10PM (#18417029) Journal
    Have people already forgotten the advantage of digital? If you have an analog tape, every time you make a copy of it, the quality will be degraded. But with digital, you can make a million copies and the final copy will be the byte by byte equivilent of the original. So what if CDs only last 10 years before becoming unusable? You can make another copy! So what if this guy wouldn't have been able to recover after physical damage to his media....if it was important, he should have had digital offsite backups! And those backups would have been 100% equivelent to the originals.

  • 1% = Total Loss? (Score:4, Interesting)

    by JesseL ( 107722 ) on Tuesday March 20, 2007 @12:12PM (#18417057) Homepage Journal
    If losing 1% of the data on a CD means the data is a total loss, doesn't that say to you that you should be using a file system and data formats with more redundancy and parity?

    Of course for the ultimate in durable electronically readable storage you should be burning everything to PROMs [wikipedia.org].

  • Apples and Oranges (Score:3, Informative)

    by Overzeetop ( 214511 ) on Tuesday March 20, 2007 @12:16PM (#18417133) Journal
    The tape had analog data on it. Analog, as we all know from years of television and radio, is very forgiving of damage. CDs are digital data. There is error correction, but for normal playback/reading devices there is a limit beyond which they simply give up trying. The data is perfect or its gone for those machines.

    Sad to say, tape dies too.

    What is more interesting is the use of compression (and rights management, though if your originals are encrypted you deserve to get screwed - physical security comes first). With analog and simple stream encoding of time domain data (such as audio recordings) much data can be recovered using an external benchmark for the time code. Compress that data and lose your parity and you're totally hosed.

    I've never been a proponent of compressed or encoded backups. Sure they save space and add a layer of "security", but that comes at the cost of flexibility should damage occur.

    Of course, as has certainly already been mentioned - with digital data, you have the luxury of making multiple perfect copies as well as the ability to perform automated checks of that data, mostly possible without user interaction necessary.

    Othwise, stone tablets have the best track record so far, though the storage density is a bit on the light (or should I say heavy?) side.

    • Re: (Score:2)

      by geekoid ( 135745 )
      Tape creates perfect copies as well.

      BEar in mind, we are not talking about cassette here.

  • I've said it before and I'll say it again... (Score:4, Funny)

    by eno2001 ( 527078 ) on Tuesday March 20, 2007 @12:18PM (#18417167) Homepage Journal
    ...the solution is simple. We need a way to take a quantum snapshot of the whole of the Earth at least once every 24 hours and then to send that data out into space as a broadcast in all directions. To retrieve the quantum structure, we'd simply pop out of a wormhole near where the data is passing and retrieve it, then retransmit it back to here and reconstruct the Earth as it was before catastrophe struck. The nice thing about this is that if we can find another M class star like Usolia (our sun), we don't even have to beam the data through the wormhole. We could just intercept it near the star and start the assembly process there. Point-in-time restores for the whole of the planet. Imagine that. You're welcome.
    • Point in time restoration, brings back all the bugs and vulnerabilities too. Unless you could apply all the security patches released after you have check pointed Earth, it will be pwned in no time.

    • Re: (Score:3, Funny)

      by inviolet ( 797804 )

      We need a way to take a quantum snapshot of the whole of the Earth at least once every 24 hours and then to send that data out into space as a broadcast in all directions. To retrieve the quantum structure, we'd simply pop out of a wormhole near where the data is passing and retrieve it, then retransmit it back to here and reconstruct the Earth as it was before catastrophe struck.

      That service is already available [magrathea.px]. However, only the ultra-rich can afford it, and what with the whole galaxy in a bit of a rec

  • Remember the "Domesday Book" (Score:4, Interesting)

    by hopbine ( 618442 ) on Tuesday March 20, 2007 @12:23PM (#18417245)
    In the 1980's they digitized the Domesday Book. Trouble was the format they used is now obsololete. The good news (apart from still having the origional) they have re-inveted the wheel. http://news.bbc.co.uk/2/hi/technology/2534391.stm [bbc.co.uk] for details.
    • Things like this frustrate me. I'm the last one at my workplace still using a system as simple as tar and gzip. But you know what? I'll be the only one that will be able to easily read my archived data in 5 years. We get these companies like HP coming in and trying to sell us extremely fragile technology and I just have to laugh. What is the point of a backup that lasts 100 years if you don't have the resources to read it. When it comes to archives and backups, simple is better. Human readable plaintext whe

  • Umm.. (Score:5, Insightful)

    by phasm42 ( 588479 ) on Tuesday March 20, 2007 @12:25PM (#18417287)
    If a CD had been submerged in water, it would've been fine. There's no point in making the comparison if it wouldn't have been damaged in the first place. They need to find a better example.

  • Mission-critical archives and backups (Score:3, Insightful)

    by zuki ( 845560 ) on Tuesday March 20, 2007 @12:28PM (#18417335) Journal
    There is much that has already been documented and guidelines exist [cdpheritage.org] to guarantee somehow the short to medium-term preservation of digital assets; this particular link is for audio-related digital assets, but data is all the same...!

    A combination of multiple sets of magneto-optical and tape backups maintained in separate locations, all temperature and humidity-controlled environments should easily yield 25~30 years shelf life, which guarantees that by then we'll hopefully have found better long-term options to transfer these to.

    I am transferring most of my 15 to 20-year old audio DAT tapes digitally with no problems. Good brand-name CD-R's (like Tayo-Yuden) kept out of the light and at a steady temperature seem fairly resilient so far, but there has been batches which over time have developed 'rot' or layer oxydation, which sometimes renders them partially or wholly unusable.

    DLT tapes are so far the most trouble-free type of media I have encountered, but with only 10 years to go back on, not sure that is accurate.

    Z.
  • In order to make digital backups that are more durable than their analog counterparts:
    1) Make a digital copy
    2) Repeat step 1 until your digital copy takes up as much physical space as an analog copy would
    3) For no reason, lay out all your digital copies in such a way that the whole of them create an analog copy
    4) For fun, Pretend what you've done is "holographic storage"

  • Sorry to spoil the fun (VXA tape format) (Score:3, Informative)

    by mihalis ( 28146 ) on Tuesday March 20, 2007 @12:39PM (#18417543) Homepage

    I know I'm offtopic, injecting facts into this debate, but I thought it might be interesting to bring up the VXA tape format. It allegedly survives all kinds of abuse like freezing, see Freezing Test [exabyte.com]

    I have never tried these drives, and would love to hear from someone independent who has.

  • So You've Lost a $38 Billion File (Score:3, Insightful)

    by jeevesbond ( 1066726 ) on Tuesday March 20, 2007 @12:41PM (#18417569) Homepage

    Chappies in New Brunswick:

    'I've had audio tape come into the archives, for example, that had been submerged in water in floods and the tape was so swollen it went off the reel, and yet we were able to recover that. We were able to take that off and dry it out and play it back.

    From an earlier /. article:

    No problem. You reach for your back up tapes only to find out that the information on the tapes is unreadable.

    Quick someone tell the author of: 'So You've Lost a $38 Billion File [slashdot.org]' that everything is alright! New Brunswick had data that was submerged in water, tape so swollen it was off the reel; they still managed to recover it.

    And don't come out with that: 'Polar Bear ate the backup tape' excuse again!

  • Just because a bit or a million bits of a CD or DVD is unreadable does not necessarily make the entire contents unreadable. CDs broken in half can be taped or even glued back together, and with a little patience most of the data can be recovered. Avoid this situation :-|.

    Sometimes I've not been able to recover disks that have been damaged beyond a certain point. But I've never lost a CD because it got wet, or had one become unplayable because it warped. I keep backup tapes in a water-resistant container (
  • Only cuneiform tablets have truly stood the test of time. Even printed paper can't match the 5 millenia of a solid piece of dried clay.
  • It seems to me that one answer is to increase the reliability of the way we store information on digital media so that it is better able to handle corruption and loss.

    For instance Reed-Solomon codes or Tornado codes can be used to break data up so that you can use a subset of the pieces to reconstruct the original signal. After chunking things up into small enough pieces that these codes are practical to apply, you can scatter the chunks across the disk or across multiple disks. This general sort of thing a
  • Sure, stick a tape in water and it might still maintain enough data for recovery. But how about running it past a magnet? Oops, there goes your data, and nowadays there are a lot of things that generate magnet fields which - while they might not be enough to completely fry all you data - do a good job of scrambling magnetic media.

    Now I'm not going to suggest that a box of DVD's bought at Walmart in a 50/$25 pack is a good replacement for tapes, but in cases with proper handling and storage, optical-based
  • The examples used are comparing analog data on tape vs. digital data on cd.

    Who backs up all their data on CD/DVDs? I don't know of any enterprise who puts their long term backups on CD/DVDs. Everyone still uses tape. It is just in digital format vs. analog format.

    And like other posters have pointed out, there are more serious concerns such as DRM and equipment resources.

    And again, like other posters have pointed out, you can make perfect digital copies. You cannot do that with analog.

  • From the article:

    "Theoretically, life is far more documented than it's ever been in the past," said Fred Farrell, manager of private sector records. However, he adds it's not unrealistic to think all that documentation will be lost to deterioration over time.

    Is this really that bad a thing? Do we really want everything preserved forever? Obviously, there are important exceptions (historical records, artwork, family "heirloom"-type information, etc. but do we really want all the day-to-day minutia to be so d

  • TV DVD recorders (Score:3)

    by quacking duck ( 607555 ) on Tuesday March 20, 2007 @02:38PM (#18419451)
    As much as I like the convenience of digital recording (random access especially), I can see where they're coming from. Especially from a consumer electronics standpoint.

    Our one, and so far only, experience with our DVD recorder (the TV/Video kind) illustrates why we haven't gotten rid of our VHS tapes yet.

    Least steps to record onto a new VHS:
    1) pop tape in
    2) press record

    Least steps to record onto new DVD (-RW in our case):
    1) pop DVD in
    2) wait 10 seconds before format options come up
    3) wait 1 min for format to finish
    4) select recording option (quality setting, etc)
    5) begin recording

    At the end of an hour-long show, I finally hit "stop" on the DVD recorder. In earlier, shorter tests it took about 30 seconds to write out the information for that hour. This time, it failed for some reason.

    End result: the whole hour of recording was lost.

    All the other nice features that would've come with recording to DVD were flushed right down the drain, for the simple reason the damn thing can't even guarantee that what I recorded would, in the end, actually be available to play back!

Slashdot Top Deals

C'est magnifique, mais ce n'est pas l'Informatique. -- Bosquet [on seeing the IBM 4341]

Close