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Data Storage Media

Best CD or DVD Recordable Media for Longevity? 81

icepick72 asks: "I have recently purchased a collection of music (on CDs) for a music group that had their final tour last month. Without getting into copyright issues (I'm writing from Canada -- not that it necessarily makes a difference) I would like to know if any CD-R media on the market supports longevity. In the past Slashdot has discussed the degradation of CD/DVD media. How do I go about knowing what the good media is nowadays, and how to get a decent price on it? One company uses this foil or that foil while another uses polywatchmacallit. Looking for good suggestions, and an archived discussion on Slashdot for future reference."
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Best CD or DVD Recordable Media for Longevity?

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  • External hard drives (Score:5, Informative)

    by harrkev ( 623093 ) <[gro.ylimafnoslerrah] [ta] [dsmfk]> on Saturday November 19, 2005 @08:34PM (#14072915) Homepage
    Well, you could rip it to your favorite format and throw it in a spare hard drive with an external hard drive USB (or firewire) box. This should be able to hold even .WAV files (unless they released over 200 albums).

    When USB begins to be phased out for something faster, simply buy whatever the newest hard drive and interface flavor-of-the-month is, and copy from the old HD to the new.

    If you are really paranoid, you can just get two drives, and keep them in separate places (preferably separated by 1000 miles or more).

    And if you add to that CD-R backups, then you should be prepared for anything.
    • The nice thing about Hard Drives is they tend to grow geometrically. Get a backup drive now, and by the time you need another backup drive you can get one proportionally bigger for the same amount of money. Wait a while longer, and grow it again at the same cost.

      You should be doing this already anyway, for your photographs and other valuables, so it doesn't take any extra effort.
    • Magnetic media, even if perfectly shielded from external magnetic fields, is not permanent. Magnetic hysteresis is not perfect, the recorded data will break down over time just due to entropy, even if the magnetic media remains stable. That is the whole point of doing an optical recording on a permanent media like DVDR, the recording will be stable as long as the substrate is stable.

      In other words, using hard drives as long-term backups is a stupid idea.
      • That is the whole point of doing an optical recording on a permanent media like DVDR, the recording will be stable as long as the substrate is stable.
        So tell me, how long does "permanent" DVD-R Media last? No-one can tell for sure. All the dyes age with time, you get reflectivity issues, etc.

        And as the GP said, as your need for backup storage increases over the years, you keep buying newer drives of larger capacity, relegating the old ones to the scrap heap (or just kept as old snapshots). So you only keep
  • They suck (Score:2, Insightful)

    by Threni ( 635302 )
    You just can't spend 30p or whatever on a piece of mass produced plastic and expect it to last more than a year or so. It's just not going to happen. DVDs are the worst - I've written slowly to write-once DVDs and not been able to read it back immediately after, or maybe it'll work for a few months then stop - it has very few scratches and I treat it really carefully but still a few files don't work. I'd stick with hard disks.
    • Re:They suck (Score:4, Insightful)

      by lubricated ( 49106 ) <.moc.liamg. .ta. .plahcim.> on Saturday November 19, 2005 @08:50PM (#14072970)
      It's funny how the public has grown to accept a defective product and then shrugs and says, well at least it's cheap.
      • Like floppies? Seriously, Those things don't last 20 minutes for me. I just use a flash drive now. 1GB is enough for anything I need to transfer, anything else stays on my 200GB hard drive.
        • yeah like floppies. Seriously what is up with them, it used to be that you could put your documents on a floppy manhandle it for a week and get your data no problem. These days even new floppies protected in a case go bad instantly. Then again floppies have been obsolete for what 8 years now.
          • Some of us still have to code for 486 PCs which use dos,and don't have USB ports or CD rom drives! Floppies seem ok to me in terms of reliability.
          • For kicks i booted my c64 and tested out my 20+ year old floppies (damn), they still worked, not bad for sitting in a garage..

            I have 9 year old CD's that still work without issues, my old win95 email archives test ok.

            Copy them every few years to new media, save originals, problem solved.

          • Last time I rebuilt my computer, I ripped out the floppy drive completely. I hadn't used the thing in years, and 1.4MB of storage isn't useful for very much these days anyway. I filled the space with another hard drive, which is more useful to me.

            Getting on-topic for a change, I have personally found the most reliable media for off-line storage to be the TDK 700MB CD-R. I have occasionally had problems with Kodak and Imation media, and I avoid the no-name brands completely. I also use the TDK DVD+R media, b

      • What do you mean by "defective"? If you mean receiving a batch of unburnable media you can very likely return it to the manufacturer for replacements, I have. If you mean we accept the fact that a product breaks down, I'm afraid that's how it is for most things.

        Are you upset that your car isn't like the day you drove it off the lot a few years later? Or ask a person living by a body of water what it does to their furniture and pianos. Are those defective products? DVD-Rs are cheap but have a limited life

  • It's tough to say. (Score:4, Insightful)

    by munpfazy ( 694689 ) * on Saturday November 19, 2005 @09:03PM (#14073015)
    The NIST site that hosts the article you mentioned has some tips on specific media types, but trying to buy them in small retail quantities isn't alway easy. There's rarely any guarantee that on opening two identically packaged boxes from a media company you'll end up with identical media.

    For some anecdotal info (and links to even more anecdotal info), check out the section 7 of the CD-Recordable FAQ

    http://www.cdrfaq.org/ [cdrfaq.org]

    To add one more statistically questionable story to the pile, I know several recording studio techs who swear by Mitsui. They're a little more expensive than generics, but you can buy 50 or 100 disc pack from the company itself (or an official distributor) and be reasonably sure of what you're getting. I've had only good experiences with them myself.

    But then I've had very few bad experiences so far with any media, and all of those have involved generics with gummy printable labels applied to them, and all were given to me by other people. (My own paranoid technique is to label disks only with a non-alcohol based felt tipped pen.)

    On the other hand, if you're goal is archiving the irreplaceable (rather than just stuff that will be expensive to replace), it's hard to beat a pair of hard drives which contain flac (or, if disk space is cheaper than processor time wav) files and checksums for every file. Every year or two you plug in each drive and make sure all the files are good, and when it starts to become hard to find systems that will interface with your old drives, you transfer everything to new ones. When you can pick up a 200 gig ata drive and a USB hard drive enclosure for well under a hundred bucks, it's hard to argue against that sort of strategy. You could do the same with DVDs or even CDs, of course, but checking them becomes a manual hassle.

    In any event, make two copies of everything so that if one goes bad, you are likely to have a backup. Keeping one somewhere other than your house doesn't hurt either.

    • I swear by Mitsui archival gold CDs for archival storage of my digital photos. I use a thermal printer to label them: much more legible than pen and the discs are designed to work well with a thermal printer.
    • My professional photographer father swears by the mitsui dye dvds and never applies any sort of marker or label. Usually it is a post-it note attatched backwards to the inside cover of the case (though I think he should be writing a reference number or something on the inner hub of the disk just in case).
    • Mitsui is now making archival grade DVD-Rs. They are about $100 for a pack of 50.
  • If you're really serious about the longevity of your data, you probably should get it backed up onto a commercial dvd. Otherwise, just use a DVD-R or something.

    I dunno what the other guy was complaining about when he said he couldn't read it straight after he burnt it. Here's a hint: Maybe it's not the disc? Maybe it's your burner. I've got DVD's lying around the place from years ago that I've burnt at 2x and they still work.

    Anyway,
    Serious: Commercial DVD
    Not so serious: DVD-R
    Half assed solution: Put the f
    • I'm betting it's the burner. From working in a PC shop, and seeing what stupid people buy every day, it's the cheap burners and media that are responsible for this crap. LG burners, blah.. BenQ burners, puke. Pioneer never let me down, nor Plextor (except for their crippleware firmwares). I buy only Ritek/Ridata media which I consider very good for the price, but if I could find a reliable source of TDK I'd probably stick with those. I'd rather pay 50% more and get something that works everywhere ever
  • Try this: (Score:2, Interesting)

    by dcapel ( 913969 )
    rippify to a nice open codec that won't lock you out, then upload to gmail. My bet is its totally safe for years and years to come...
  • I'm using some of these Gold DVD-R's. After doing some research I picked these. They are supposed to have a shelf life of 200 years or something if treated and stored properly.

    I bought them at this Canadian retailer...

    http://ncix.com/products/index.php?sku=16000 [ncix.com]

  • I'm really not sure what the difference is, but the music CDs I made back when CDRs were expensive ($10 for 5) still work great for me ... that's like back in 99 - 00. Now, newer CDs seem to go bad in a 3-6 months. Not sure why.
  • You don't want to buy better media, you want more copies. Keep at least 2 copies of every cd, and make new copies every 1-2 years to avoid degredation problems. Its cheaper and more sure.
    • Only ideas, put a copy of the codec you're using on the disks.

      Preferably with source code if you can find it, that way you'll be able to compile it in years to come.

      Create a hash with a common hashing algorithm, when computers become exponentially faster (Think Quantum Computing)you might be able to extrapolate the data back (Should not be impossible with some additional data such as filename, size, and a brief excerpt).

      You could store ALL the hashes on a single disk.

      There hasn't been a storage gene
      • Hashes are one way. There are an infinite number of files that have the same hash. The tricky part is finding them.
        • >Hashes are one way.
          >There are an infinite
          >number of files that
          >have the same hash. The
          >tricky part is finding them.

          But if we limit ourselves to files of a specific size, then we get away with a finite (but unpleasantly large) number of files.

          In that case, all we have to do is design a quantum computer able to pick the one that is best described by the liner notes.

          Granted, it's a bit harder than just buying some extra media in the first place, but certainly a lot more fun.
          • Assuming a cryptographically perfect 8 bit hash, and assuming we're hashing a 16 bit number. There are going to be 2^8 (256) collisions.

            Assuming a cryptographically perfect 4kbit hash and a 16mbit file, we have 2^(2^24 - 2^12) files (2^16,773,120 files) that match that hash. If the hash isn't cryptographically perfect, this number is the average number of collisions. Note that the files may only differ by a bit or two.
      • Re:Redundancy (Score:3, Informative)

        by ColaMan ( 37550 )
        You use something like - it basically splits your data into blocks and then you can define the amount of redundancy you like. [quickpar.org.uk]

        So say you have a file and running it through par2 with 50% redundancy gives you 100 blocks. All you need at a later date is 50 (any 50) of those blocks and you can recreate the file.
    • I back up my data to a dvd-rw and a dvd-r. This way I am sure that I am using two different types of disks. Since the actual manufacturer of disks is generally not known until you use some special program to read the disk, I don't trust different names on the disk to mean different chemical formulations.

      I also have a backup linux box that use to mirror all of my data.

      I also have a fireproof safe that I put backup hard drives in. I store the hard drives in army ammo cans, as they are the only truly air
  • Basically, you want the surroundings to be chemically inert. We always put all our DVDs and CDs in ZipLock Freezer bags, Quart size. The package says they have a "FreezeGuard Seal", which means that you can expect that all moisture is excluded.

    Freezer bags have extra thick plastic, which provides good, slippery, mechanical protection, too.

    If you expect to store the DVDs and CDs for a long time, put the Quart size bags inside Gallon size Freezer bags.

    For extreme protection, go to a shoe store and ask them for those little packets of dessicant (moisture remover) that are in each box of shoes. They'll give them to you free. Put one in each Gallon bag. I don't put them in the inner bag because the impurities in the dessicant granules might be abrasive.
  • Verbatim (Score:2, Informative)

    by dlichterman ( 868464 )
    Verbatim is awesome stuff......they have a limited lifetime warranty! I have never had problems with bad discs. They are sometimes more expensive, but well worth it.
    • Nothing against Verbatim, but lifetime warranties mean nothing on CD or DVD media. All that means is that if you mail in the now-defective disc, they'll send you a blank replacement disk. So it costs them a couple dollars including postage to replace your defective discs, but you still lose your data. And how many people actually mail in their defective discs instead of chucking them in the trash and buying a new spindle?
      • Well they advertise a 100 year shelf life usually on their datalife media. I just burnt my first DVD+R-DL.....oooooohhhh pretty!!!!
        • Yeah, but the only way to prove that conclusively is to wait 100 years and see if it's still readable. Even if the majority of their discs last that long, there will be plenty that don't.

          I've taken to running dvdisaster on my RW discs before I erase and reuse them to see if they're still reading well. It doesn't have error statistics, but if the read speed drops a lot in an area of the disc, it probably means it's having trouble reading that part of the disc--just don't run dvdisaster while your system is
    • I know "AZO" is advertised as more safe than some other organic dyes, if it's the best for real and how much better I don't know, and there are more brands which use it.
  • The original stamped CDs will out live any CDs from a burner. Create CD images from the originals and possibly FLAC files. Put the original CDs away and never touch them again. Copy the cd images to DVD and copy the DVD every couple of years.
  • by WoTG ( 610710 ) on Saturday November 19, 2005 @11:26PM (#14073485) Homepage Journal
    For photos, backups and other archival stuff to CD or DVD I've been adding PAR parity files [par2.net]. They're sort-of like RAID at a file level. Even though the initial use of .pars was for Usenet binary downloads (I think) the tools work great for any situation where partial loss of data is likely. In theory, as long as the unreadable bits of the disc are a small % of the disk, I should be able to rebuild the data. There's an article where this is tested by scratching / drawing on a CDR -- unfortunately, I don't have a bookmark. The chances are good that a disk will not go bad uniformly across the entire disk. So, the parity files should be able to recover from most scratches and a lot of bit rot.

    Plus, I feel that .par files are better than making 2 copies of the same data. For example, if you're only backing up a few large files, the odds of having both copies of the file get a few bad sectors is relatively high. I suppose you could patch over unreadable bits with a hex editor or something, but I'll take a nice GUI and relatively common software anyday.

    Although, to be perfectly honest, I just don't rely on CDR or DVDR. I keep a copy of all stuff on a hard drive too. DVD's go offsite, HD stays at home.
    • I've been looking at using dvdisaster [dvdisaster.com] for a similar reason. It was mentioned recently on one of the local sage lists I'm on, and unfortunately was too late for the asker (whose media was already corrupt).
    • If the badsectors on medium a are not on the same place as on medium b, you can use recoverdm [vanheusden.com] to merge those into one correct image.
    • Plus, I feel that .par files are better than making 2 copies of the same data. For example, if you're only backing up a few large files, the odds of having both copies of the file get a few bad sectors is relatively high.

      Why is the liklihood any higher than with .par files?

      Seems to me, .par files are rather silly on a CD format, since CDs already include multiple layers of forward error correction as part of the standard itself. If the damage is so extensize as to defeat the parity that's already alw
      • Regarding likeliness, I was thinking more in terms of recovering from a bad scratch or a bit of bit rot. When I wrote the post, I had no idea how I would easily recombine two identical but damaged files. Although, one of the other responses to my GP post recommends an intresting program to do just that.

        Regarding ECC, it's true that disks have a lot of error correction already, about 30% of a CD IIRC. However, I've still seen more than my fair share of partially unreadable CDs. I don't know the detail
  • by Myself ( 57572 ) on Saturday November 19, 2005 @11:27PM (#14073489) Journal
    Just search for "archival gold" media. A few companies make it. Most of the degradation comes from the aluminum reflective layer oxidizing, and using a gold layer prevents that. Simple, effective, and not that much more expensive.

    Personally, I prefer magneto-optical for the important stuff. Disappearance of the SCSI interface will make the drives unusable long before the media degrades.
  • You could use media that is designed for long term data retention, and it typically kept readable by design of next gen hardware... LTO tapes kept in a controlled environment.

    Not everyone has a robotic library backing up their workstation - but even a gen or two older desktop drives are obtainable. Media isn't the cheapest, nor is it great for easy access - but when your CD-Rs fail, and the hard drive you had saved the original AIFF files fails... the LTO tapes are still there.
  • by SIGBUS ( 8236 )
    For a long time, the Etree [etree.org] community has recommended Taiyo Yuden [t-yuden.com] media. Fujifilm CD-Rs used to be OEMed by TY, but not anymore.

    FWIW, I've (ab)used a variety of CD-Rs in my car CD player, subjected to extremes of heat and cold, and found that both the Imations and the TY Fujis have held up well. Scratches have caused me more trouble than environmental conditions.

    • TY is the best of the cheap CD-Rs. Mitsui are reported to the best, but the cost A LOT more. FWIW, they are made in Colorado Springs.
    • Fuji still uses Taiyo Yuden for some of their CD-Rs. When looking at the packaging, look for Made in Japan to get the TY instead of Made in Taiwan. Lately, I've only found the Taiyo Yuden in 30-paks. I gave up using anything else a long time ago, and returned the first Taiwanese Fuji CD-Rs that I bought right away.
  • by NOPteron ( 838244 ) on Sunday November 20, 2005 @04:37AM (#14074340) Homepage Journal

    Use RE-Writables, not WORM.

    RW discs:
    *blanking aneals metal-layer in disc
    *burning quick-melts spots of metal in disc, so they freeze quickly to different crystallization than the annealed "normal"
    *reading means reading the changes in reflectivity that occur ( or differences in polarization, in magneto-optical, IIRC ) in the METAL reflecting the laser-beam.

    Write Once discs:
    *new disc is "blank"
    *laser "burns" organic-dye in writing,
    *reading-laser "sees" the diff between burnt and non-burnt as less-transparent vs more-transparent, and the reflective-layer behind-it means that this is usable binary encoding. . . ( beam goes through organic-dye twice and then is read, or perhaps gets-eaten by the burnt dye and then its absence is read. . . )
    *organic-dye decays

    IF you care about archival, you then store complete versions of your files,
    with checksums and ECC on RW discs.

    IF you are using organic-dye write-once discs, then you are basing your ability-to-recover your stuff based on Estimates & Marketing Claims(tm). ..

    Cheerses

  • What banks do... (Score:5, Informative)

    by Hobart ( 32767 ) on Sunday November 20, 2005 @05:05AM (#14074437) Homepage Journal
    Well, there's what banks do with their optical media, which is have the glass master stored in a safe deposit box. A glass master for a DVD costs about $1000 , CD costs about $700. (Googled from http://www.cddvdking.com/ [cddvdking.com] ).

    Barring that, you can buy TDK professional media ( http://www.tdk.com/professional/ [tdk.com] )

    Also, googling for Archival CDR reveals a review on the subject by photo.net at http://www.photo.net/mjohnston/column53/ [photo.net], which leads to the $3-a-disk Archival stuff here. http://store.mam-a-store.com/standard---archive-go ld.html [mam-a-store.com]

    Hope this helps.
  • I don't know but now when SUN has delivered ZFS wouldn't regular harddrives in a raid setup with ZFS be close to optimal? All data is protected with a 256bit checksum and gets fixed if the system finds an error.

    Only problem is if the whole system dies (that is if it's always connected and something like the lightning struck or the place burns down and so on), I guess you could send everything over to another machine somewhere else to.

    So two separated Solaris machines with atleast 2 harddrives and zfs will d
    • Online storage is always an issue, since no matter what level of redundancy you have, if a command to erase or write over the data can be run, you're fucked. Error, virus/trojan, etc.
  • My archiving system (Score:4, Informative)

    by AmiMoJo ( 196126 ) <mojo@nOspAm.world3.net> on Sunday November 20, 2005 @11:38AM (#14075536) Homepage Journal
    I have quite a lot of data (>800GB and growing) I want to keep for at least twenty years, on a budget. Currently, I am using DVD-R.

    I only use Taiyo Yuden DVD-Rs, with a Pioneer 108 DVD-RW drive. Taiyo Yuden invented the original CD-R, and are the only company that still makes discs in Japan. Their discs have excellent quality dye, and provide good quality burns.

    When determining how to burn discs, some experimentation is needed. Try different speeds. I have found that a 12x burn gives better quality (i.e. fewer errors, no burn is perfect) than 8x on Taiyo Yuden 8x discs with my burner, but other drives may be different. Try using tools like Nero CD-DVD Speed and DVDInfo to check the number of errors, and that your drive can read the discs at maximum speed all the way to the end. Take a look at the CD Freaks forums, particularly the media tests sub-forum for more info: http://club.cdfreaks.com/ [cdfreaks.com]

    I always create parity data. Parity data, in the form of .PAR2 files, is created by QuickPAR and other tools. Basically, with parity data, if some of your actual data becomes corrupt, you can recover it. I usually create 5% parity data, which means that if 5% of my data becomes corrupt I can still recover it. If 6% becomes corrupt, I'm stuffed. So, for very important stuff, I use 10% or even 25% parity data. Remember to burn the parity data to a different disc, preferably stored in a different place to the disc with the actual data on it.

    A note about PAR2 files and DVDs. If your DVD becomes unreadable, i.e. you can't see the filesystem, rip it as an ISO image file. Use a tool that can skip errors, like ISOBuster. Then, use the PAR2 files to try and recover data from it. PAR2 is clever enough to find useful data blocks inside the ISO.

    Don't use anything silly like multi-session discs, and make sure your PC can keep up with your burner so that you don't need to rely on "just-link" or whatever they call it. Make sure you verify data after burning (Nero can do this automatically).

    Store the discs in a cool, dry place. If you are on a budget, metal "flight case" boxes with CD wallet style holders are a good bet if you keep them in a cupboard out of the light. Don't use flexible wallets. If you have the money, there are commercial storage systems designed for very old books which would probably work well.

    Also, be sure to check discs every few years. I generally test a sample of my discs once a year. If any of them show signs of degrading, such as no longer being able to read at maximum speed or high error rates, I re-copy them. My oldest Taiyo Yuden discs are now four and a half years old, and only one (which I may have mishandled) has started to fail so far.

    If you are really paranoid, you could keep the parity data on magnetic tape or hard disc. The advantage of only keeping parity data on these more expensive mediums is that it's usually only 5-10% the size of the actual data, which keeps costs down.
  • by jdclucidly ( 520630 ) on Sunday November 20, 2005 @11:45AM (#14075575) Homepage
    Verbatim's DataLifePlus brand /usually/ means that the disc is rated for a 100 year shelf life with a scratch resistant plastic. Also note that their DVD brand will have an even greater life span due to the fact that the film on a DVD disc is sandwhiched between two layers of plastic. On a CD, the film is exposed to the air.

    The discs are also inexpensive. You can pick them up from places like Provantage for under 75 cents each in spindles.
  • I still have some Kodak CDs that I recorded in 1998 and they still work perfectly, both for data and audio. About DVDs, I'm used to buy "LGs" (at least they are labeled LG, but cdrecord says they are SMC Magnetics or so), but I don't know if they are really reliable... I have been using then for about 6 months and they still work, but I don't expect it to last more than 2 years. I'm looking forward to know what others /.ers will say about reliable medias.

    Regards,
    Gustavo
  • http://www.dvdisaster.com/ [dvdisaster.com] Generates error recovery data from a DVD and writes it to a "backup" CD. Of course, you have to worry about the CD now as well, since you've got nothing protecting it, but CDs were always more scratch tolerant than DVDs. As for environmental effects, I recently pulled some ~10 year old floppy disks out of a cardboard box in a closet (Borland Turbo C) and they worked just fine, so a jewel case would probably protect optical media at least as long. S
  • Kodak Gold CD-Rs. Last I checked, they were only available in 650 MB, but I have some that I burnt 6 years ago that are just as good as the day they were burnt. They get scratched much more than my other cds, and still work much better.

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