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How To Properly Archive Data On Disc Media 120

Posted by Zonk from the yay-data dept.
An anonymous reader writes "Patrick McFarland, the well-known Free Software Magazine author, goes into great detail on CD/DVD media over at the Ad Terras Per Aspera site. McFarland covers the history of the media, from CDs through recordable DVDs, explaining the various formats and their strengths and drawbacks. The heart of the article is an essay on the DVD-R vs. DVD+R recording standards, leading to McFarland's recommendation for which media he buys for archival storage. Spoiler: it's Taiyo Yuden DVD+R all the way. From the article: 'Unlike pressed CDs/DVDs, burnt CDs/DVDs can eventually fade, due to five things that affect the quality of CD media: sealing method, reflective layer, organic dye makeup, where it was manufactured, and your storage practices (please keep all media out of direct sunlight, in a nice cool dry dark place, in acid-free plastic containers; this will triple the lifetime of any media).'"
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How To Properly Archive Data On Disc Media More

How To Properly Archive Data On Disc Media

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  • Dupe... (Score:5, Informative)

    by LighterShadeOfBlack ( 1011407 ) on Saturday March 31, 2007 @04:55PM (#18559589) Homepage
    This is practically a word-for-word dupe of a /. posting from December 11th 2006 [slashdot.org]
    • I thought this looked familiar... It is an excellent article though!

      • Re: (Score:3, Interesting)

        by LighterShadeOfBlack ( 1011407 )
        It is a good article on the pros and cons of DVD-R vs DVD+R in general, however I'm not too happy with the way the author recommends one particular brand over others like that without any hard data to back it up. It's quite possible it's absolutely true and they really are a superior brand of discs, but without presenting any numbers to support his assertion it will remain nohing more than one person's opinion.

        • Re: (Score:3, Interesting)

          by Dogtanian ( 588974 )

          I'm not too happy with the way the author recommends one particular brand over others like that without any hard data to back it up.

          To be fair, whilst I'm not claiming that I've never come across criticism of Taiyo Yuden, they seem to be consistently ranked #1 in reliability and quality. In fact, come to think of it I can't recall seeing any reviews where their media (overall) weren't the top rated.

          I believe that Verbatim (owned by Mitsubishi) are also very highly rated (except for a brief period in 2002 when they switched to a far less reputable media supplier). More info in this article. [digitalfaq.com]

          Bear in mind that a *large* number of majo

        • I'll chime in as well with a statement that I've never had problems using TY media. Of all of the media I've used (and I use a lot - doing commercial DVD authoring), TY is the only one that has never once had a problem.

          It's worth noting that this article is specifically talking about data archiving (obviously), where the +R format does offer advantages with error correction/handling. One size doesn't fit all for media however, and I still recommend using DVD-R for video DVD authoring as it has a much high

          • Re: (Score:2)

            by eric76 ( 679787 )
            I think the gap between DVD+R and set top players is pretty much decreased to the point that there isn't much difference between DVD-R and DVD+R compatibility with them.

            I saw some figures showing the percentage of "modern" DVD players and the difference in the number of models that could handle DVD+R and those that could handle DVD-R but not DVD+R was only something like 2% to 4%.

        • It's common knowledge among the CD recording crowd that Taiyo Yuden - a Japanese brand - is the top maker of media. I always buy Fujitsu brand DVDs (although not CDs, because CDs are less critical) because most of their media is made by TY. It's an issue with the proper spreading of the dyes, apparently. The Japanese have the quality control standards that the Taiwanese simply don't have (except in cases where a Taiwanese company is using Japanese equipment and methods, which does occur.)

          Check out the forum
          • Meanwhile my LiteOn is still going strong after almost 5 years of use, both as a CD burner and as a regular drive.
            • I still use a LiteOn DVD reader - which wants to spontaneously close its door whenever I open it - but I do burning on the NEC. Even the NEC's door seems more solid - when it opens it sounds like a bank vault compared to the LiteOn.

              I think the consensus of burner experts is that NEC is way better than LiteOn. I see NEC being sold by the local computer shops - but not LiteOn. With the essentially zero difference in price, NEC is the way to go.

    • Slashdot ascribes more to the "post it somewhere and let Google archive it" method. Zing!
    • It's just an archive hosted from a long-lasting Taiyo Yuden DVD+R.

    • Re: (Score:1, Funny)

      by Anonymous Coward
      Excellent, thanks. The comments there are much more intelligent.
      Oh how I miss 2006, the internet has really gone downhill since then.

    • Re: (Score:1)

      by RedElf ( 249078 )
      This is practically a word-for-word dupe of a /. posting from December 11th 2006

      You must be new here...they usually wait less than 4 days to dupe it.

  • M*Farland? (Score:5, Interesting)

    by MDMurphy ( 208495 ) on Saturday March 31, 2007 @05:02PM (#18559699)
    I'm sure it's just a coincidence that we have to articles posted by anonymous readers linking to "famous author" M*Farland, but it struck me as odd. Especially since he commented on the USB story. Could there little astroturfing going on?

    It's not like we haven't seen that before ( Roland P* )

  • Patrick McFarland? (Score:5, Informative)

    by MysticOne ( 142751 ) on Saturday March 31, 2007 @05:03PM (#18559703) Homepage
    I know who he is. I would've never called him a "famous free software writer" as he was labeled earlier today, and if he's "well-known", it's not for being a writer. The way these summaries are worded, as well as the fact that both stories today were submitted by "an anonymous user", just makes me think that somebody is looking to boost their site's traffic today. Nevermind the fact that the article is old and has already been linked to on slashdot before.

    Anyway, just seemed fishy to me. That's my $0.02.
    • I never read the articles on Slashdot. That's what Playboy Magazine is for.

    • Re: (Score:1, Informative)

      by diablo-d3 ( 175104 )
      Don't look at me. Whoever this anonymous coward is, he/she must have a sense of humor. I've written for Free Software Magazine three times I think, and one of those even made it to Slashdot. As much as it rocks to be linked to Slashdot twice in one day, I do not, and have never, described myself as some famous author, nor as as a famous coder, nor as any of the other things I've seen.

  • Why bother with optical? (Score:3, Interesting)

    by Anonymous Coward on Saturday March 31, 2007 @05:18PM (#18559895)
    A 500GB hard drive is like $150 these days and 1TB drives are just around the corner. Drop one into a $10 USB enclosure and backup your stuff using rsync. To do it right, do this twice with 2 different drives and store them in 2 different physical locations. I don't care what fancy pants brand of DVD-R you use, a magnetic solution is still superior in both durability and simplicity (try backing up 100GB of data using a DVD writer and a hard drive, then tell me which one took longer).
    • I agree, and it's faster to archive and restore. You'll want to store it in a cool, dry place, in an environment that's as static-free as possible.

    • Re: (Score:1)

      by Lucky77 ( 777803 )
      Just about 10 years ago $150 is what a 500 MB Maxtor drive would cost. Having the much denser drives now changes the criteria concerning backup and archival methods. DVD's, regardless of being -R or +R, still seem flaky to me. Perhaps as the technology matures (increased reliability) along with a magnitude increase of density then I will take another look at utilizing DVD technology for archiving.

      I just bought two 500 GB drives ($139 each) last night for the very same backup strategy that you suggest. I

    • Re: (Score:3, Informative)

      by Hatta ( 162192 )
      At $150 a 500gb drive is $.30/GB. At american-digital.com (my personal favorite place for bulk media), I can get 16x Taiyo Yuden dvd+r media for about $.60/disc; which, at 4.7GB/disc, works out to $.128/GB. So hard drives are more than twice as expensive per gigabyte as DVD+R.

      • Re:Why bother with optical? (Score:5, Insightful)

        by Anonymous Coward on Saturday March 31, 2007 @06:16PM (#18560595)
        I think you're really making their point. Optical media just isn't cheap enough to bother with it anymore, and with the prices of magnetic storage always decreasing, there's even less of a reason to use optical media.

        Yes, you'd save a few bucks initially by using optical media. But then you have to split all your data in evenly sized 4.7GB archives or such. Label them all manually. Waste hours swapping hundreds of discs by hand. Catalog all these discs (number them, keep a database or something0. And they take LOTS of physical place to store.

        I got tired of looking for a specific DVD. After an hour of flipping thru pages of those (expensive and large) CD wallets and not finding it, I gave in, and bought several TB worth of HD space. Now if I want a movie, it's there, listed alphabetically and all. Jewel cases suck too -- too brittle, wastes space too, and a waste of money.

        HDs have a very high density (the new 1TB drives will store more than a spindle of 200 DVDs), requires no storage cases, no constant media swapping, no splitting to fit the size of media, etc. It's all-around better! Restoring stuff is almost instantaneous. You never have to look for a specific disc. Transfer speeds are great. Everything is sorted alphabetically inside folders/directories... What more could you ask for?

        Want to make a new copy - to another format, or just onto newer media? It takes what, 15 seconds to start a copy job using HDs? With optical media, you'll be swapping discs by hand for months.

        Plus, HDs are not read only -- you can make monthly backups on them no problem (full or differential). Using optical media this is a pain. The cheap discs are write-once, and even if the rewritable discs were cheap, it still takes a while to erase them all manually.

        Backup/sync jobs can be totally automated using HDs. Want to do daily differential backups? Schedule it once, never have to bother ever again. With optical discs you'd be swapping, labeling and cataloging media 365 days a year... What a pain.

        Long story short, I might as well backup all my storage on 1.44MB floppies instead of optical discs. It'll take hundreds or thousands of them, and you'll spend countless hours swapping media and splitting stuff to fit the media size. NO THANKS!

        • Re: (Score:1)

          by Lucky77 ( 777803 )
          Please mod this AC up
          • Yup, the simplest, fastest and most reliable method of backing up data is a portable USB drive. Dunno about the cost but if they aren't cheaper now they will be soon. The author of the article shills for DVD+R quite effectively but how long will it be the standard? What's new? Blu ray?

            HDDs keep getting cheaper in terms of dollars per byte stored. They are also getting faster, smaller and more reliable. Why bother with anything else?

            • Re: (Score:2)

              by kbahey ( 102895 )
              I am doing exactly that since mid least year.

              Bought two 250GB disks (Cdn$70 each on sale), and two USB enclosures (Cdn$27 each).

              Works out of the box with Linux.

              A cron job does an incremental dump to BOTH disks once a day. Once a week, a level 0 dump is performed and several versions of that are kept.

              Details here:

              - Setting up a hard disk USB 2.0 enclosure for backup under Linux [baheyeldin.com].
              - Ubuntu Linux backup of a laptop using a USB enclosure and the dump utility [baheyeldin.com]

              Drawbacks?

              1. The silent enclosures have no fans, and are
        • I ask myself this a lot: how reliable are HDDs in the long term?

          Say you use them for archiving. It is better to go the NAS route and have them always on, or powered down when not in use? How about a USB enclosure only connected when in use? How reliable is an almost-new used-it-once HDD that has been sitting on a shelf for five years?
          • Comment removed based on user account deletion

            • Re: (Score:2)

              by AmiMoJo ( 196126 )
              I don't mind it not being random access, which is why I currently use DVDs. But HDDs are cheaper and easier to use because they are read/write. You can recycle them by deleting old data too.

              Still, there are no hard numbers on reliability. RAID is not a backup solution, it's about uptime and availability which is pointless in this context. It's no good having two identical disks if they both get corrupt or the heads seize up after a few years.

              One argument against alawys on is that it is more prone to electri

          • Re: (Score:2)

            by kbahey ( 102895 )
            I have an always on setup using USB enclosures, but some enclosures are flaky and can't stay up.

            Ideally one would power them off and even remove them to an offsite backup regularly, but the convenience of not having to go into the basement/computer room every day makes it more convenient to keep them on always.

            See my comment here [slashdot.org] for more details.

      • Re: (Score:3, Interesting)

        by Master of Transhuman ( 597628 )

        What's your time worth? As someone said, backing up 100GB of data - something I do periodically and I do it on DVD - takes time. I back up over 200GB of data off my machine to DVD - it takes me most of a day of personal attention. Backing that up to an external hard drive would take much less time and require nothing more than starting the transfer (depending on how the files are being selected of course).

        That said, DVD (or tape, of course) is better for offsite archival storage than disk in many, if not al

      • Re: (Score:3, Interesting)

        by KokorHekkus ( 986906 )
        And add to this that failure of one optical disc is less catastrophic. If one optical disc fails you have a lot less loss than if one drive does... of course that means more work but there is always a trade-off, isn't there. You could argue that you should have more than one drive but the same goes for optical disc.

        From personal experience optical discs might need one more step though: to verify that the write was ok. I don't have any optical discs that have failed me yet after I started to check writes.

      • Re: (Score:2)

        by zoftie ( 195518 )
        Perhaps you'd like to calculate the time, that it takes for you to swap in and out and keep track of the media. Unless you have some automated solution to make backups on multiple cds with robot arm actuators replacing dvdr's and marking them, with likes of inkjet.
    • What will you do when the lubricant evaporates? Buy a scanning tunneling microscope?

    • Re: (Score:1)

      by shoor ( 33382 )
      I've thought about doing that, but, what bothers me is that if the hard drive fails, it could take out ALL the
      data on it. (Granted, there may be ways to recover some or most of the data, unless the drive is just utterly
      destroyed in a fire or something, and if it was a fire, your whole box of DVDs would probably be wiped out
      too). Also, with DVDs or CDs, one buys incrementally to archive; one could put
      some money in an interest bearing account for instance, though it's a trivial amount. Finally, there's a
      ps

    • Re:Why bother with optical? (Score:4, Insightful)

      by pogopogo ( 464296 ) on Saturday March 31, 2007 @06:24PM (#18560667)
      There is a difference between an archive and a backup.

      An archive is something that is stored in a safe location for possible use later, but also to save for posterity.

      A backup is used to keep current data in two locations in case one set of data is lost.

      Hard drives are fine for backups. For archives you want write-once media that can't be easily (or even possibly) erased.

      Two different solutions to two different problems.

      • Re: (Score:3, Funny)

        by MMC Monster ( 602931 )
        This article is not a dupe. It is simply a backup of the /. article of December 11, 2006.

        • Re:Why bother with optical? (Score:4, Interesting)

          by MMC Monster ( 602931 ) on Saturday March 31, 2007 @07:05PM (#18561171)
          On topic: People should use something like par2 to create some fault tolerance so that when a few bytes go bad (or a scratch develops) the entire DVD+/-R is not toast.

          I typically create data DVDs with 30% redundancy information (though smaller percentages are probably more than adequate) with par2create, and store those par2 files on the same DVD. That way I survive the little scratches and can recreate the data.
          • Doesn't the ISO9660 format already have a certain amount of redundancy in it?

            Not saying that using PAR2 to create some additional redundancy is a bad idea, but I don't think that one-bit errors are totally disastrous automatically, if you've burned your data in a normal format.

            Not sure what UDF does, though.

            Although it's not as if PAR2 is a particularly exotic format, just in case it drops out of common use in the future, I think I'd still put a plaintext copy of the source code for the reassembler on every
            • Yes, all(?) optical media has ECC already.

              The problem with ECC at the disk level is more of a user interface problem. When a disk starts failing (and the ECC is kicking in), you don't get notified. At least, not until it's too late and the ECC can no longer fix the errors. Attentive users may notice that the disk is having trouble seeking / reading but most users won't.

              When you add PAR2 data to a disk, you create a window of time where you can recover the data after the disk shows obvious ECC errors.
          • I do a similar thing but I store the PAR2 files on another dvd for safety.
    • I've had hard drives fried by failing power supplies. Sometimes you get lucky and replacing the electronics from an identical drive works, sometimes it doesn't. I've never heard of a CD or DVD drive's laser suddenly burning holes in the disc.

      Ditto with mechanical shock -- a DVD will survive a lot rougher handling than a harddrive will, even if the latter's heads are parked.

      There are always trade-offs.

      • " I've never heard of a CD or DVD drive's laser suddenly burning holes in the disc.

        I've had cd drives that ate the cd, and one time ejected a cd at high speed. Think frisbee, not coaster. When a disk fails at 52x, your PC will sound like an unbalanced washig machine.

        Ditto with mechanical shock -- a DVD will survive a lot rougher handling than a harddrive will, even if the latter's heads are parked.

        Drive over a hard drive, then put it back in the machine - it'll work. Just drop your 100-spindle sta

    • Try this: backup your data to an external hard drive. Then, shake it violently over your head a few times or drop it to the floor from 4 feet. Then try and read your data from the drive. I don't trust mechanical magnetic drives for backup as far as I can throw them!
    • what we need is a media-quality firesafe combined with an internal hard drive, a massively ruggedised hard disk... would need a special channel for power and data (would have to be firewire or usb2)... so if your house or office burned down, you'd have the equivalent of an airplane black box data recorder.

  • Which leads to... (Score:2, Insightful)

    by BlurredOne ( 813043 )
    This just brings up the question:

    Is there a point to digitizing human cultural pieces that has survived for 10,000 years onto media that will fail in 10?

    • Re: (Score:2)

      by Surye ( 580125 )
      That's the benefit of digital, it doesn't degrade over copies, so each generation of storage media gets a perfect copy from the last.

      • Re: (Score:3, Insightful)

        by the eric conspiracy ( 20178 )
        That's the benefit of digital, it doesn't degrade over copies, so each generation of storage media gets a perfect copy from the last.

        That is certainly not true, and even worse digital is less resiliant to errors than analog formats.

        • Re: (Score:2)

          by Kjella ( 173770 )
          "That's the benefit of digital, it doesn't degrade over copies, so each generation of storage media gets a perfect copy from the last."

          That is certainly not true, and even worse digital is less resiliant to errors than analog formats.

          If there are errors, I don't recall them ever happening in the copying, they happen in storage. And while single bit errors can happen, with checksums I can verify that I have files that are closing in on 20 years old that are perfectly preserved. With PAR files I could even re
      • Very true. And I dont dispute the merits of digital.

        However.... There are plety of cultural pieces that have survived in harsh environements, wars, etc. and are still in relatively good condition. Put a cd outside for 1 year and its fubar. Thats the point I was trying to bring across.

        We may be able to make perfect copies indefinetly, but at some point in the future, someone, somewhere, will have the great idea of digitizing art, and destroying the original, then leave the only copy of Mona Lisa out
        • That's why I upload my data to eMule in an encrypted .rar, and named as some specific exotic type of porn. I just let the rest of the world archive my data.

          Sure, my HDD might die someday, or the DVDs rot, or whatever... But then I just go re-download all my critical files.

          Looks like I have about 300 backups distributed around the globe of this one chunk of stuff! =D

      • Re: (Score:1)

        by Lucky77 ( 777803 )
        Good Point. One needs to keep the old stuff updated into current technologies though. I know of individuals that have information stored on reel to reel tapes that have little possibility of ever being copied to current media leave alone being reformated into a usable format.

        Lucky77

      • Or, if you want to do away with the "generations" altogether, engrave the digital data into a rock — with suitable instructions on how to decode, of course. That way your data becomes immortal, more or less. On the other hand, you would probably need a mountain-sized rock for the average TIFF.

    • It also brings up a partial answer: Not using consumer-oriented optical discs.

      A more complete anwer to your question: Yes, it is worth it. Existing peices of history may have "survived" thousands of years, however I'm not aware of anything that has survived that time completely intact. And despite all the modern preservative techniques at our disposal we still cannot completely prevent the degradation of physical artifacts. Digitised content on the other hand can be copied infinitely and perfectly preserved
      • It's not that I don't see the merits of digitizing for preservation. My issue is with the belief that digitization is the only answer to preservation. I rue the day that we no longer work at preserving our original pieces just because they are stored 'perfectly' in a digital format.

        Formats will change, but paper will always be paper. Marble will always be marble. And art (in all its forms) will always be art.
    • I think perhaps you miss the point. Storing something digitally is not something you do because a single digital copy is somehow better than a single analog one. You do it because you can make an arbitrarily a large number of duplicate copies of the data and therefore keep it safer than a single analog one could ever be. Don't just have it at the Smithsonian... have a million perfect digital representations all over the world.
    • I don't think it has to be an either-or decision.

      If an artifact has existed for 10,000 years, only a fool would suggest that we destroy it and only retain copies that are on an untested medium. However, if some new medium makes the data more convenient and useful, then there's no downside, really, to making it available in both -- keeping the old format and also copying it into a modern electronic one.

      Just as a trivial personal example, I have a lot of photographic slides and negatives. Some of them (the on
    • Yes. "Preserving" stuff (artifacts or information) isn't really just about chucking a bunch of junk in a clean, dry place. To be useful, it must be accessible.

      Remember "Raiders of The Lost Ark"? How at the end, some old guy hides the Ark in a government warehouse? You might write your important cultural stuff in stone, but if nobody can find it, it might as well not exist. Another example: the beard of the Sphynx is sitting in a back room somewhere in the British Museum. But nobody knows it's there, so who

    • Re: (Score:1)

      by steevc ( 54110 )
      That's why people like the Long Now Foundation [longnow.org] are looking at media that could be readable in thousands of years time.

    • Is there a point to digitizing human cultural pieces that has survived for 10,000 years onto media that will fail in 10?
      Ask that to anyone who doesn't actually own the human cultural pieces but still wants access to the information.

    • whilst the data density of stone tablets is quite low, if carefully stored they're pretty much readable indefinitely!

      • Re: (Score:1)

        by e9th ( 652576 )
        It's the "carefully stored" part that can sometimes be a problem. Cf. Exodus 32:19.

  • Disks BAH! (Score:2, Funny)

    by iminplaya ( 723125 )
    I prefer cylinders [tinfoil.com]. If they were good enough for grandpa, they're good enough for me.

    Note: With I can gather from the name of the site, it appears they might also sell hats, but I couldn't find a link.
  • And since the optical media is so cheap, make multiple copies of each disc, with data shuffled around on the surface on each copy.

    That way, any "spot defects" will be very unlikely to hit the same data on every copy. Making the whole redundant backup set last many times longer.
    • Uhh... I seem to recall that CDs have enough spots on the disk to hold like 1.8gb of data, but there needs to be heavy redundancy, and thus only 650mb can be used.
      • There is no redundancy like that. Or else you'd already see "1.8GB: use at your own risk" discs. Or CDs that are a lot more loss resistant than they are now. Or at least a mention in the article we're discussing of this triple redundancy.

        • Re: (Score:2)

          by AusIV ( 950840 )
          From Wikipedia [wikipedia.org]:

          CD-ROM Mode 1, usually used for computer data, divides the 2352 byte data area defined by the Red Book standards into 12 bytes of synchronisation information, 4 bytes of header data, 2048 bytes of user data and 288 bytes of error correction and detection codes. These codes help prevent the data from becoming corrupted, which could lead to errors for executable data.

          This means on a 700 MB CD, you have ~840MB of space. Audio CDs use this extra space because data corruption isn't too significa

          • Well yes, there is a filesystem, ISO9660, which eats some data as overhead. And the 288 bytes error correction/detection. But that's not data redundancy, it's really detection, not correction. For correction it would have to have 1168 bytes of correction for 1168 bytes of data.

            And you can't use the "extra" bytes above 2048 per frame for data, because you need the filesystem to do what it does. If you encoded in CDDA, which is no filesystem/overhead, you start losing data immediately on different players tha
            • It is an error correcting code -- IIRC one that's designed specifically to correct the types of writing errors which are common on optical media. Remember, correction does not imply that it can correct all media failures -- there is always some type of media failure which no amount of error correction can handle (say, destruction of the whole universe).

              Also, the error correction/detection is not dependent on having any particular file system on the medium. Any data CD (regardless of file system) has the dat
              • We're talking at different levels. There is a little error correction data to compensate for the error rate of every writing tech, no matter how expensive - just fewer errors for a lot more money, asymptotically. And every filesystem does have it - I never said that it's specific to one filesystem, though I was replying to a given filesystem. The CDDA format is not a filesystem, doesn't have it, and can deal with corrupt data by dropping it before output.

                But that's not error correction for the data decay we

                • And every filesystem does have it - I never said that it's specific to one filesystem, though I was replying to a given filesystem.

                  The level at which error correction on a CD/DVD occurs is not the file system. I can do the equivalent of dd=/dev/HUGE_FILE of=/dev/cdwriter and error correction will still be applied. Of course you may have a different notion of what a file system is, but generally a storage layer isn't considered a file system unless you actually use it for organizing files... which the "sect

  • Good experience with DVD-Rs myself (Score:4, Informative)

    by bouis ( 198138 ) on Saturday March 31, 2007 @06:05PM (#18560467)
    A quick primer: you can "error scan" DVD+/-R media with a drive that supports it. CDSpeed, a [free, IIRC] utility distributed by/with Nero, can easily save these scans. DVD enthusiasts often compare their scans... cdfreaks.com is a great discussion site.

    Some media have been observed to degrade fairly rapidly, others are quite stable. About a year ago, and again recently, I scanned a number of relatively old DVD-R discs [backups, uh, owned by a friend] burned from fall of 2002 on. You can see my post here:

    http://club.cdfreaks.com/showpost.php?p=1733269&po stcount=294 [cdfreaks.com]

    Funny thing is that most of the discs I used were of a brand widely lambasted as "cheap ____" and I was told that they wouldn't last six months. Curiously enough you can see that the cheaper "Princo" media has held up better than the "gold standard of the day" Riteks [although both are much better than some]. You can also see that one of older discs was scanned recently, and more than a year ago. It shows almost no degradation during that time [and what it does could easily be attributed to the aging scanning drive].

    The CDFreaks forum has a lot more scans, including of older media. If you've got some discs and are worried about their aging stability, here's a good place to start:

    http://club.cdfreaks.com/forumdisplay.php?f=33 [cdfreaks.com]
  • april fools. i wonder how many people didnt pick up on this. you do know it is april first somewhere right ;)
  • I started burning CDs when a burner was $500.00 and only available as a SCSI drive. This is one rare times I'm glad I was on the bleeding edge. Back then you had to know what gold/gold , blue/gold , blue/blue. Was it made in Japan or Taiwan. Turn your screen saver off. Buffer under run protection did not exist. A 4x burner was fast.

    Now people complain if you can't burn faster than 24x. Ask them what color their media was and you'll get something like, "Its magenta with Sony written across it." Peop
  • A friend and a very competent sysadmin said to me (maybe 5 years ago) "tape sucks".

    He told me in many ways, why any kind of disk archive was better than tape. I've thought about that conversation many times.

    My conclusion FWIW, is the same as everyone knew half a century ago. Accessibility-density-longevity... pick = two.

  • Fails to mention MO (Score:3, Informative)

    by zoftie ( 195518 ) on Saturday March 31, 2007 @07:06PM (#18561179) Homepage
    Magneto-Optical media is used by medical facilities where archival time length is paramount. Such as:
      - http://md5.ca/~pavel/md.jpg [md5.ca]
      - http://tinyurl.com/2cu7zv [tinyurl.com]
    MO drives are a bit costly, but if you have important media its worth it. Besides cool look for neo's warez stash in Simulcara book. Quoted guaranteed archival time is over 40 years in most cases, and they continually improving the technology, compared to driving the costs down of the generic blank media market of CDs/DVDs.

    • "Magneto-Optical media is used by medical facilities where archival time length is paramount."

      My last magnto-optical media died from the click of death, you ignorant clod.

    • The format is a no go. Way to go Sony, once again!! In the begining, i loved Minidisk players and i still own a Mrz-30 that still works well. I have a Net-Md and it sucks!. I see where i work they have 3.5 MO disks. you can only order them from Japan or somewhere like that. It is a shame that they never caught on. they have very good sound quality, 20-20k. The ATRAC3 format would even hold up to 5 hours of music compressed. The interface was the problem. Oh well, back to work...

  • Other tips: (Score:2, Funny)

    by pizzach ( 1011925 )
    Other tips for longativity:

    - Use acid free CD-markers when marking
    - Do not use as a coaster like your America Online CDs
    - Do not play Frisbee outside with your CDs (Exposes to direct sunlight)
    - Chewing reduces durability
  • The article admits that Taiyo Yuden's formulation used to be the best, until they improved all of the others!

    We're to use Taiyo Yuden's "Super Cyanine" "stabilized" Cyanine dye, because for a short time, it was the best dye. But then the article goes on to admit that TDK' "metal-stabilized Cyanine" is rated for the same shelf life. Then it goes on to admit that the "Metal Azo dye" I see listed on the brands I've been buying is rated for a longer shelf life than either of the previously mentioned ones,
  • ... was available other than in Japan. I think there is an importer of 12X media now though. Though DVD-RAM can't be used in regulated environments that specify true WORM media, for other (small, SOHO) data backup chores, it would be the thing to have (with 12X media). NewEgg has 12X DVD-RAM drives for under $40. Personally, I think they are purposely keeping DVD-RAM media away so as not to suppress Blu Ray adoption. Wikipedia has a pretty good writeup on DVD-RAM. The history of optical media for computer d

  • Use dvdistaster (Score:4, Interesting)

    by arose ( 644256 ) on Saturday March 31, 2007 @10:34PM (#18563159)
    No matter what format you choose create error correction data [sourceforge.net].

  • DVD Writable sucks badly as archival technology. (Score:4, Interesting)

    by gweihir ( 88907 ) on Saturday March 31, 2007 @10:47PM (#18563271)
    Sorry, but if you have to select media and burner based on some black magic, then the technology is entirely unfit to be used for any archiving. Archival media give you ensurances like 30 years data lifetime in any combination. You can already get that with MOD. MODs have >50 years data lifetime and drive makers will allways support the lasdt three media generations (currently they are supporting all, i.e. the last fife generations and that wor reading and writing). The only DVD technology that is somewhat comparable is DVD-RAM with cartridge. But that seems to have zero market share in the computer business.

    My conclusion is that either people do not care about their archived data or that the number of, e.g., lost baby- and wedding-photographs is not high enough yet.
  • Here [wiebetech.com] is an excellent article on the true cost of archiving to CD/DVD. I have grown to distrust optical media more and more. The only CDs I burn now are KNOPPIX discs, OS install discs, etc. Anything important I archive to a hard drive. I have an external SATA enclosure that has a removable tray.
    • they just happen to sell a superior solution. For offsite archiving, I prefer something I can slip into an envelope and mail cross-country without being concerned about it being dropped or subject to magnetic fields.

      For workstation-size data sets, I use a drive mirror for short-term and DVD+R for long term... and looking forward to terabyte recordable in 5.25" form factor which should be available in a few years.
  • Asfar as i see dvd ram is not discussed
  • develop the disk platters with MagnaSee (Reeves, 1956 product) and impress the platters in potter's clay or slip clay. then fire the clay, and you have a permanent archival copy.

    I can't reply to this april fools stuff any more, my head hurts.

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