Burned CDs Last 5 years Max -- Use Tape?

Lam1969 writes "Computerworld has interviewed Kurt Gerecke, an IBM storage expert and physicist who claims burned CDs only have a two to five-year lifespan, depending on the quality of the CD. From the article: "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data 'shifting' on the surface and thus becoming unreadable to the laser beam." Gerecke recommends magnetic tapes to store pictures, videos and songs."

I guess it depends on how you treat them

[bilbravo (763359)]

I have some CDs that are burned copies (although I'd call this great quality cds, not cheap storebrand with no backing), stored in a CD wallet case that are easily over 5 years old... still work great.

Re:I guess it depends on how you treat them

[letxa2000 (215841)]

I have both audio and data CDs I burned way back in, what, 1996? They still work perfectly. The first audio CD I burned at that time has spent the last 10 years in my car in the heat of Mexico. Still works perfectly.

Re:I guess it depends on how you treat them

[rouge86 (608370)]

I have a disc that is 5 years old, and I labeled it with permanent ink. It still works and defies this article and the ones that say that I can't use permanent ink on my CD's.

Re:Ziplock bags don't breathe,...

[Futurepower(R) (558542)]

Another comment:

This is a quote from the story: "His recommendation: a hard-drive disk with 7,200 revolutions per minute." That's a way to have secure storage?

That's a recommendation? It's quite obvious that the author of the referenced story, John Blau, has no technical knowledge.

Another quote: "Kurt Gerecke, a physicist and storage expert at IBM Deutschland GmbH, takes this view: If you want to avoid having to burn new CDs every few years, use magnetic tapes to store all your pictures, videos and songs for a lifetime."

I suppose that article was written by a public relations person and was published because someone was paid. Magnetic tapes are NOT reliable, in my experience.

Re:I guess it depends on how you treat them

[Yewbert (708667)]

Closer than the article, but still missing a crucial distinction. -R and -RW are very different. -R is pretty much as you say - the ink/dye/CHEMICAL layer that's written to is burned; this layer is not the reflective layer.

In -RW media, the write layer is a metallic layer that isn't "burned" but merely heated differentially to create regions of either more-crystalline or more-amorphous metal when cooled; these regions have different refractive characteristics, and can thus be distinguished by laser. This is why it's rewritable - the melting>glassy / melting>crystalline process is reversible.

http://www.usbyte.com/common/Re-writable_CD.htm [usbyte.com]

...contains a succinct but detailed explanation as good as any I've seen (many other sources confuse refractivity with reflectivity, and don't clearly explain that the write layer and the reflective layer in a -RW medium are indeed different layers).

So, to blather on only a little bit longer (too late?), to respond to the immediate contention in this subthread, the reflective layer is in NO case the very same layer as the data is written to. But, in practice, the top coating containing the reflective layer on any -R medium is so bloody thin as to make no difference. If it becomes separated from the surface of the disc, you're hosed. If you want to see how thin this layer is, stick a CD-R in a microwave for a few seconds, till it flashes, and observe the resulting flakes.

Back to the bigger question, the paragraph in this crappy article that says "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data "shifting" on the surface and thus becoming unreadable to the laser beam" is needlessliy confusing things by including "CD-RW" in the statement - to conflate a REVERSIBLE phase-change/metal layer-writing process with a PERMANENT burn/dye layer write process is stupid and confusing to anyone who doesn't know better. Whose fault it was to include that, I dunno.

This still leaves the question open as to whether the sorta-stable phase-change alloy ages in substantially the same or else a very different way than the permanently altered -R ink/dye layer, and whether any such difference affects the useful lifespan. I've NEVER seen this specific question rigorously answered. I'd love to hear from anyone who has links or direct info.

If you say so...

[Moby Cock (771358)]

Magnetic tape? Ok

Anyone know where I can download an MP3 jukebox for my Vic 20?

Re:If you say so...

[DaveM753 (844913)]

Dood...you should upgrade to the Commodore 64: it has the SID chip -- much better audio. Now..where did I put my Datasette?

Re:If you say so...

[zoeblade (600058)]

Anyone know where I can download an MP3 jukebox for my Vic 20?

No, but there was a program listed in Zzap! 64 once that let you play audio tapes using your Commodore 64. Type in the program, press play on tape, turn your TV's volume up, and listen to something with slightly more signal than noise.

Conflicts with other studies

[Nom du Keyboard (633989)]

Haven't other studies confirmed much longer lifetimes in the past for CD-R? After all, we've had CD burners for longer than 2-5 years. Is this only a surprise because absolutely nobody has ever gone back and tried to read an old disc? Somehow I'm still doubtful of his conclusions.

Re:Conflicts with other studies

[metternich (888601)]

I've had burned CDs die very quickly as well though. Therefore the only solution is to upload your music onto P2P netwroks to save the back up copy fair use entitles you to.

Re:Conflicts with other studies

[dosquatch (924618)]

The CD-R / CD-RW industry has said from the beginning that the product lifespan of these discs is between 50 and 200 years [osta.org]. The problem with this is that this media has not been around nearly so long, which means that these "studies" are based on the same WAGs that give our new researcher his 2 to 5 years, they're just reaching different conclusions. Only time will tell.

Re:Conflicts with other studies

[TIMxPx (859220)]

Yes, studies sponsored by the CD media consortium. Wonder who sponsored this latest study?

Umm, the tape backup consortium?

5 years max?

[blanktek (177640)]

I have CDs that have lasted 10 years with no errors. Obviously 5 years is not the maximum life. Perhaps the maximum EXPECTED life.

Depends how you define lifetime

[Solandri (704621)]

Keep in mind that CDs have a ton of error-correction coding on them. You could lose probably 20%-30% of the bits and still have a working CD. I suspect by "lifetime" the guy means when dye layer starts to deteriorate. Error correction can get you past that point, but you end up with a CD that reads fine one month, then "suddenly" develops dozens of bad sectors.

Most serious photographers I know re-burn their archives every one or two years.

Re:5 years max?

[hackstraw (262471)]

I have CDs that have lasted 10 years with no errors. Obviously 5 years is not the maximum life. Perhaps the maximum EXPECTED life.

I've had CDs that were about 5 years old that went bad. They went from the burner to a CD book, and maybe 2 to 5 out of about 100 were bad. I didn't investigate, or maybe even screwed up the burn (win2k), and I used good media, mostly Mitsui.

I believe the tape recommendation to be absurd. If CDs are in the though process, there must not be too much data here. Especially in th

Re:5 years max?

[duffbeer703 (177751)]

Maximum life is irrelevent. I could draw a picture in the sand with a stick and protect it from the wind for several years -- that doesn't make it a good media to store things in.

If your goal is to preserve data, and there is a 10% chance that exposure to moderate heat will render the media useless, it's time to pick another media.

Re:5 years max?

[gihan_ripper (785510)]

What does that mean? By 'maximum expected life' you surely mean the expected life of the medium, that is, the mean of the lifetimes of a good sample set of CDs. When a lifetime is quoted, e.g. for lightbulbs, the manufacturer doesn't guarantee that the product will fail when its expected lifetime expires!

Re:5 years max?

[BushCheney08 (917605)]

I have a few data CDs that I burned in 97/98 that I recently pulled out. Worked fine for me. Then again, they were burned with a good quality Yamaha drive. I'm sure some of the stuff that I've burned more recently with a cheapo LiteOn drive (which died just after a year of use) won't fare so well.

CD-Rs with a 100 year warranty

[OverDrive33 (468610)]

We've known that CD-Rs will degrade for a long time. Hispace [hispace.com] have recently launched a new range of CD-Rs aimed at digital photographers. These disks use 24 caret gold to help add stability to the disks. As a result, they come with a 100 year warranty.

Your porn will be around for decades after all!!

Re:CD-Rs with a 100 year warranty

[LordSnooty (853791)]

If they can guarantee 100-year lifespan with a bit of gold then surely the problem with normal discs is over-stated. And that guarantee - does it cover the disc, or the data? No good in 30 years if I want to look at my "family album" - I don't want a blank disc to replace the degraded CD, I want the data.

Or my money back?

[winkydink (650484)]

Great. I lose hundreds of precious photos. They give me a buck.

I can attest to that...

[ajiva (156759)]

The wedding photographer for my wedding gave me a DVD of the video + photos. After about two years the DVDs were so degraded that I could not a single DVD player would recognize them. And that's with light usage... Now I keep important DVD as images on an external hard disk.

Re:I can attest to that...

[jridley (9305)]

I have had many problems with DVDs. I've had media that degrade quickly, and also writers that cause discs to degrade quickly. Every disc I wrote in late 2003 is bad. They started going bad after only a few months (in some cases, days).

I switched both burners and media and now have no problems. However, I still do a 100% verify, and don't totally trust DVD-R. For stuff I *really* want backed up, I put a PAR2 set on the disc, and I burn both DVD and at least one CD copy for offsite.

BTW I found that some really crappy DVD-ROM drives will read almost anything. All of those hundreds of bad discs that I have? I bought a shitty CompUSA DVD-ROM drive for $35, and it will read them all, even though NO other drive I own will read them (I tried Sony, 2 NEC, 1 Pioneer and 1 Lite-On DVD-R drives, plus Teac, Pioneer DVD-ROM drives). I have NO reasonable theory why this is, but the damn thing just reads anything. I'm glad of it too. I discovered this when I realized that my shitty $40 mintek set-top DVD player would play the discs and "better" players choked, so I decided to try a crappy DVD-ROM drive. So I can now make new copies of the messed-up discs.

Re:I can attest to that...

[aonaran (15651)]

Usually the reason why crappy DVD-Video players play back things that don't play in other players isn't because the pickup is better, but because the decoder is more tolerant of non-standard discs. Some discs that play on PCs and these cheap players just won't play on the better ones because the disc itself is not made to the proper DVD spec. Most often I've seen either improperly encoded video or missing AUDIO_TS folders. Next to that is not having the files organized properly on the disc, or the wrong file system (ISO vs UDF)

Nothing lasts forever

[digitaldc (879047)]

When I first asked this question of how long CDs will last, I was told about 70 years.
I was also told that to lengthen a CDs shelf life, always store them vertically in a cool dry place, and clean them from the inside ring to the outer edge in a straight line.

I found an article from the Optical Storage Technology Association and they say it depends on the initial CD quality and handling.
According to this article, unrecorded CDRs last about 5-10 years, manufacturers claim recorded CDRs 50-200 years and recorded CDRWs 20-100 years.

More info: http://www.osta.org/technology/cdqa13.htm [osta.org]

Re:Nothing lasts forever

[Cthefuture (665326)]

Also do not touch the coated side of the disc. Cleaning the read-side isn't generally going to degrade it in any way, even if it's scratched those can be buffed out of the clear plastic. The problem is the other side of the disc. The colored/laminated side is the material that gets written to. It's not protected with a thick plastic coating like a real pressed CD. Touching, mashing, or exposing that laminated side to pretty much anything out of the ordinary will shorten the life of the disc.

Dutch Study?

[OzPeter (195038)]

I can't remember all of the details, but I am sure there was a Dutch group who took a sample of all of the available CDs at the time, burnt data onto them, put them in storage for 2 years and then re-tested the disks quality. Their results showed that all of the disks had significant degredation.

OK .. here is a link to a news report of that study

http://www.cdfreaks.com/news/7751 [cdfreaks.com] This link includes a link to the original Dutch article

To quote:

"The tests showed that a number of CD-Rs had become completely unreadable while others could only be read back partially. Data that was recorded 20 months ago had become unreadable. These included discs of well known and lesser known manufacturers."

 

Some things that degrade CDs

[Billosaur (927319)]

• Using them as coasters
• DRM
• Leaving them on the dashboard of your car
• Contact with corrosives (orange juice, Bill O'Reilly, etc.)
• Using them as shuriken

Use intelligent distributed databases

[Arthur B. (806360)]

The best way to preserve data, imho is storage independent. Suppose you want to archive your family photos. Sure you can put them on a hard drive... then you can use raid, hard drive will be replaced regulary and the probability of a simultaneous failure being low you dramatically increase the lifespan of your storage. The same could be done on the internet with a P2P network dedicated to long term storage. You divide your files into chuncks and calculate a hash. Peers download it and keep it on their machines. You just have to keep signatures of your chuncks, you can do that on highly reliable mediums, like grave it into stone if you wish. The P2P network automatically polls for chunks and ensure redundancy by pushing rare pieces to clients. To ensure collaboration, you can upload only a fraction of what you host. Some sort of bittorrent expect it's rather a bitpool.

Photography's loss

[Alioth (221270)]

I've mulled this occasionally, but I suspect the late 20th century and early 21st century will become a mini-dark ages (at least for personal or family things).

The reasons for this:
1. depressingly high failure rate of hard disks
2. lack of long term storage media
3. obsolete formats

As for tape, DLTtape (invented for the venerable VAX) is supposed to be able to last 25 years in good condition. How many people buy DLTtape drives? They aren't cheap and the tapes are not cheap. They are about the only thing with the capacity to store all your photos and video on one cartridge.

Digital photos and video seem like great things (and are: I'd hate to have to edit my videos the old fashioned way) but there is a sting in the tail that most people won't expect. If I want to look at a photograph my Dad took in 1972, I just pull it out the draw and look at it. No maintenance has had to be done on that photograph - it's just been stored in a cool, dry, dark place.

Digital data on the other hand needs periodic maintenance. If a format you've used becomes obsolete, you have to go through and update your entire library. You have to periodically back it up. You have to periodically cut it to media like CD. How much family history have people lost already due to dead hard disks, and not realising the need to continuously back up and format shift? Even if a DLTtape cartridge is still intact and readable in 75 years time, will there be anything to read it? Will JPEG decoders come with everyone's device to view photos?

Re:Photography's loss

[jridley (9305)]

1. depressingly high failure rate of hard disks

I find hard discs insanely more reliable than they used to be. I was building PCs in the 80's and I experienced the wonder of buying a full 20-count box of Seagate hard discs, and have EVERY DAMN ONE OF THEM FAIL IN 3 MONTHS.

I currently have 8 Maxtors and Hitachis of between 160 and 250 GB spinning in 3 machines at home. Most are > 2 years old. No problems. My older 40 and 80 GB machines have been given to friends to use in their older machines. They haven't had any failures either. I can't remember the last time I had a hard drive fail.

If your case is such that your hard drives are hot to the touch, don't blame the drive for failing. I think that's what causes most of the failures.

Re:Photography's loss

[kabocox (199019)]

How much family history have people lost already due to dead hard disks, and not realising the need to continuously back up and format shift? Even if a DLTtape cartridge is still intact and readable in 75 years time, will there be anything to read it? Will JPEG decoders come with everyone's device to view photos?

I'll play it right back to you, How much family history was lost because only grandmama had the only copy of the pictures and there wasn't any way to easily copy them? Do you have "a" family photo a

Old and incorrect news

[digidave (259925)]

Not only have the early deaths of CD-Rs been greatly exaggerated before, but even the lifespan of pressed CDs were (are?) hotly disputed. In the early 80's I heard all about how CDs would last forever because each play didn't degrade the quality ever so slightly like it did with cassette tapes and vinyl records. Then in the late 80's a group of researchers determined that CDs would probably only last ten years, for whatever reason.

I got my first CD-RW drive when it was a $700 2x model well over ten years ago. The first things I burned were a bootleg Tragically Hip CD and a few rented Playstation games. I still play that Hip CD and recently I dugg out my Playstation collection to use with the epsxe emulator and they all still work great, though I can't remember which of my burned games were copied when.

I have had a few CDs and DVDs go bad, but they've always been really cheap media. Even cheap CD-Rs have been ok, but I have noticed that cheap DVD-Rs can be very poor quality and sometimes the data won't last through the night. These are usually identifiable because at least half the time the data will be corrupt straight out of the burner. You don't have to spend a lot to get good media, just don't get the cheapest media you can find.

after 5 years

[CaptnMArk (9003)]

I just recently tested ~120 cds from about 1999-2002.

Attempting to read them with a DVD drive failed many discs.

But reading with a CD drive I was able to read all of them (after some cleaning) except two (most files were readable) that were scratched.

It seem there is some difference between DVD and CD drives.

Most CDs were burned with 2-8x speed, I almost never use >16x today.

Tapes, yes, but...

[the_rajah (749499)]

The concern I have is whether I had a working drive to read the tapes with in 40 years.. Oh, nevermind, I'm 60 now, so that probably won't be a problem for me personally..

Instead of tape why not drives for long term?

[portwojc (201398)]

Isn't the cost point close enough yet to just use hard drives instead for long term storage and not be too bad?

You can pick up OEM 250GB hard drives for around $100. Toss in a $50 USB case or a SATA case and you're looking at $1.67 a GB storage. Plus you're not limited to 4.5GB file size.

Sure drives fail but you won't be spinning them that often. I'm begining to think it may be worth it for the long term. Then use the USB drive or SATA as needed and if need be burn a disk.

Re:Instead of tape why not drives for long term?

[Beryllium Sphere(tm) (193358)]

Experience with other mechanical objects stands up and asks a question.

Will the lubricant in the bearings go sticky if the drive is on a shelf and never spun up? Someone out there must have direct knowledge.

The issue is that most (most complicated, powered) machines with moving parts need occasional mild exercise.

Re:Instead of tape why not drives for long term?

[flaming-opus (8186)]

Absolutely.
Disk drive are cheap, fast, and relatively durable.

I work in the data archive field, and we don't see optical jukeboxes anymore. I think HP still makes one, but everyone else is out of that market. The preferred method is high-speed tape, but there's an entry cost for a low end changer (about $10,000) that makes it prohibitive for desktop users. second disks are a fantastic way to back up data, and you're seeing that even in the enterprise space. IT can't compete with tape in GB/$, or in some of the archival automation, but it's getting close.

The important thing with disk, just as it is with tape and with optical, is to make AT LEAST 2 backups, and to store them in a different place. I don't know how many data centers I've walked into where the tape library is sitting in the same rack as the raid, and they don't use the vaulting features. Yeah, you're protected against a disk failing, except if the failure is in a fire, or a flood.

If you care about your data, get a three drives, a safety deposite box, and a firebox.

NIST Study

[goosman (145634)]

http://www.itl.nist.gov/div895/gipwog/StabilityStu dy.pdf [nist.gov]

NIST Did a study that shows up to 30+ years of longevity that is totally dependant on handling and storage.

Re:Museum Archives

[Guppy06 (410832)]

Those are records. I don't know about you, but I don't have an LP-ROM drive.

Re:Museum Archives

[BushCheney08 (917605)]

This guy [rca.ac.uk] has one. There's even a few pics [rca.ac.uk] linked at the bottom of the page. Perhaps he'll let you borrow it.

Re:Museum Archives

[3TimeLoser (853209)]

Yeah, except that seek time would really suck -- no matter how quickly you could pick up and move the tonearm.

Re:Museum Archives

[Merle Darling (33121)]

I don't know about you guys, but my data always feels "warmer" when I read it from an LP-ROM. I can't explain it any better than that, you can just FEEL it, man! CDs are cold and digital, there's no love there.. Look, all I'm saying is that when I'm in the mood for some soulful gaming I bust out my copy of Quake4 on vinyl, none of this crap you'll find on CD (or worse, DVD) feels RIGHT, MAN!! VINYL FOREVER!!11 DEATH TO THE OPTICAL OPPRESSORS!!1111

Screw that - I'm going back to stone tablets

[tomhudson (43916)]

The article says to use magnetic tape because the CDs degrade.

So does tape. Unless you're the BOfH, in which case you have a tape safe. But you can't use that to store tapes - its not climate controlled, and you've got too many bodies hidden in it anyway ... but ever tried to read a 10-year-od tape on a new machine? I gave up - it was easier to connect to a serial port and just dump the whole database over the course of a week, its that bad. Then another day for updates. Todays USB and Firewire will be the next generation's serial ports.

So, use a hard drive?

Leave it sitting on a shelf too long and you get "stiction" - so that's no good either. And have you even TRIED to access a 10-year-old drive in todays machines? The bois tries to auto-config, and the machine won't boot.

Zip disks? Hahahah click of death hahahah (I've got several zip drives that are "unzipped")

Paper printouts? Well, those are good for a few decades, but not exactly portable ... anyone care to figure out how many acres of trees a hex dump of a 200-gig drive will take?

Nope, stone tablets - to hit anyone over the head with who thinks that there's any real long-term solution other than to just re-copy to the latest format and pray.

Re:Screw that - I'm going back to stone tablets

[Fordiman (689627)]

Gonna do some math here.

We'll assume that one can reliably retrieve data from a sheet of paper at 200 dpi.

At 200 Dpi, with reasonable page margins of 0.5" per side, you have 1500x2000 (2.86M) potential dots. Assume one bit per dot. That's approximately 0.36MB per page per side. Add one line of dots per side for alignment.

Since a page is evenly divisible by 5000 bytes, lets start there. 75 5000 byte blocks per page; each 5000 bytes will include:
64 bit address (8-bytes)
64 bit CRC (8-bytes)
Data (4984 bytes)

Additionally, since paper is (currently) a read-only media, we can preprocess the data using squashfs, thus assume that 4984 bytes is actually holding approximately 4k to 8k of data after compression and filesystem overhead.

(4k to 8k)*75==(300 to 600kB) per page, per side.

Thus, it would take roughly 175,000 pages, printed both sides, to equal a 200Gb hard drive. At 6ppm, which is pretty standard for a cheap laser printer, that would take 20 days to back up, not accounting for paper jams, toner or sleep.

Re:Screw that - I'm going back to stone tablets

[Shadow Wrought (586631)]

Just to add some weight to the equation, 100,000 pages of paper (a pallet) weighs roughly a ton (all those years at Xerox were good for something;-). So your "back-up" would weigh in at right around 3,500 pounds, or the weight of a Run of the Mill Sedan (RMS). As we all know, RMS is also the abbreviation commonly used when prolestizing about Gnu. Gnu is an anagram for "Gun."

So, the moral of the story- it'll take a ton of work, but it's worth a shot.

Re:Just don't drop them!

[WuphonsReach (684551)]

This thread also strikes me as funny because I'm in the middle of archiving about 800 VHS tapes to DVD. Many are 15-20 years old, and I've been surprised at how well most of them still work. I wonder if the DVDs will last as long, but I figure it'll be easier to move the data off them since it won't have to be done in real time.

1) Burn 2 copies, store them in physical separate locations.

2) Don't fill the discs to the brim. Only encode about 3.8-4.0GB of MPEG2. Fill the rest of the disc with PAR2 files stored in the VIDEO_TS folder (prefixed with the letter 'z' so they appear on the edges/end of the disc).

I render my DVDs to disc first, add the PAR2 data, then create the ISOs with ImgTool Classic before burning to disc. I make sure that my block size for PAR2 is a multiple of 2048 bytes (CD/DVD sector size).

Even if you can't copy individual files off of the disc, tools like ISO Buster or ddrescue (or dd-rescue) can read the disc back at the sector level. That lets you pull as much information as possible back off of the disc. Assuming you don't have more bad sectors then recovery data, QuickPar (or the open-source commandline tool) can chew on that extracted data and rebuild the files.

I did about 100 VHS tapes a year or two ago. I still have a bunch more to do in the coming year.

Re:CD Presses

[Wavicle (181176)]

Gold reflective layer CD-R's with a stabilized pthalocyanine dye have an expected shelf life of 200 years.

That's 4 times longer than the expected life of an aluminum reflective layer pressed CD.

Re:Burned CDs last 10+ years

[Winckle (870180)]

The tape companies, obviously.

Re:The only permanent solution

[Daniel Dvorkin (106857)]

Have your army of minions engrave all your really important data on clay tablets. Then try to make sure the tablets are stored in the basement of your palace when it burns to the ground, so the clay gets well-fired. Thousands of years from now, archaeologists will marvel at your beautifully preserved backups. They'll call it "cuneiporn."