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CDs, DVDs Eyed For Long-Term Archival Use
Alien54 writes "Computer scientists at the National Institute of Standards and Technology (NIST) are launching an effort to develop specifications for 'archival quality' CD and DVD media that agencies could use to ensure the procurement of sufficiently robust media for their long-term archiving needs (i.e., 50 years and longer). See the press release at the NIST site." The research involves "...enclosed chambers that use temperature and humidity changes to artificially age the media some 20 years in only six weeks."
Are they still working?
Honestly,
I've got CDs that I burned just 2 years ago, and my CD drive has trouble reading them - no scratches, it just appears that they age waaaay to quick. I know a lot of people who keep photos on CD, I hope they realise that it's not so permanent.
Maybe something good would come of this. I'd actually be willing to pay out $5 to $10 to get a CD that once burned would stick around for a while.
tom-george.comBecause geeks rate higher t
The only sure way to archive data is to keep it on a network-attached device - and migrate it regularly with changes in technology. No removable media is foolproof as hardware can break down at a time when it can't be repaired or replaced. Ask anyone with a Betamax video collection or, more relevantly, the BBC, who had great trouble reading their not-very-old Domesday archive on laserdisc. BTW, that's not a really small computer in the photo, it's a really big CD!
When I am king, you will be first against the wall.
Only if you're a crappy parent.
I've been a parent for two years now and feel younger than I did before!
As for aging 20 years in 6 weeks, I got that beat.
You will need:
1) Six packets of cigarettes.
2) A large bottle of tequila.
3) An unventilated room.
Start smoking the ciggies, then drink the tequila. When (if?) you wake up next day, you'll feel like you've aged 50 years.
Ok that method will take care of the plastic, but what about the embeded data layer? Will that get the effects of the increased ageing?
Always going forward, 'cause we can't find reverse.
We just had a baby girl (yes, even geeks need to reproduce). So people ask "what can we bring the little gorgeous thing?" (they don't have to sit through nights of "woaAAAHHH!") I've figured that the best thing would be presents that she can open when she's old enough to appreciate them, like on her 18th birthday.
DVD players may still be around in 2021, after all I can still read 3.5" floppies. But DVD media has a shelf life of 5-7 years AFAICT, several older DVDs I've tried recently don't work anymore. CDs may be less delicate, resist better.
But if you wanted to give someone a digital present (say a bunch of their baby photos) for 18 years hence, how would you go about it?
This was going to be an Ask Slashdot, but (a) I'm too tired, and (b) the whole "what can I give a gurgling baby" thing is not really stuff that interests geeks.
Ceci n'est pas une signature
Discs in fact are way better method of storage than traditional tape storage due to ease of accessiblity. However, in order replace tape for long term archiving, more has to be done than making durable discs.
:). I do not know exactly how but they must have something to charge us enoromous amount of money for recovery. :)
The other major fact is Recoverability. It's not unusual to find defective tapes before their end-of-life and we must send them to experts for retrieval of important data in them. They've technologies to recover the data, like baking the tape(yeah, bake them in oven, but please don't do it with your kitchen oven
I'm not sure if existing technology could effectively recover data from aged, defective discs. That's something we must consider before they could replace traditional tape storage for long term archiving.
It shows that digital still has a long way to go compared to the current UK practice of printing on vellum... in other words goats skin !!!
Quote: "... we compare longevity of 250 or 500 years [of long-life paper] with the 1,500 years of vellum"
---- The Open Source Record Label : : LOCARECORDS.COM
Yes I still have some CD's and a few of them are from the 80's.
I couldn't tell you if they work or not, because all the music I play is in MP3 format.
Why look for a 50 year solution, when in 20 years the archives will be stored on more efficient media, just like mp3's.
thank God the internet isn't a human right.
Musician's are forever asking pressing plants if they can have the Glass Master back in case they need it.... ;-)
---- The Open Source Record Label : : LOCARECORDS.COM
On the contrary, I have a 1980s Joy Division CD (go on, laugh) where the alu layer is heavily oxidised to the extent of showing bronze-coloured "flakes", and it plays just fine. Maybe I'm lucky.
When I am king, you will be first against the wall.
It looks like it will become necessary to copy everything to new media every year or so...
A common mistake is that archives (digital or otherwise) require no maintenance. In the case of digital archives you should be checking them, on an annual basis, not just for physical degradation.
A more common problem is that the applications used to create the data and/or their documentation do not exist any more, rendering the data as useless as if the physical media had been destroyed.
--
This sig is inoffensive.
On the other hand, I'm also a bit concerned with privacy, and the idea of these huge intrusive databases, or archival of all traffic over key gateways of the net bother me. But when I consider the difficulty that I have with huge amounts of data that are just a drop in the bucket conpared with this sort of thing, I breathe a little easier... Unfortunately, duplication and propogation appear to be the surest way to go, and unfortunately there is often a tendency for those who would invade our privacy to share their data for profit or reasons of control...
HaXXXor.com - Naked Chicks Teach You How To Ha
This effectively exists already. Recordable CD/DVD longevity is largely a function of dye stability. Over-generalizing, modern media support higher-speed writing because the dye is more stable. Ergo, greater long-term stability.
Unbranded media have other problems, in that frequently they're low-speed disks marked up as high-speed, so they get prematurely aged as they're written to.
Although I've got a couple of old CD-Rs that are unreadable, my MO stuff going back to 1989 still seems to be OK. So is my old PD stuff. Maybe phase-change is the way to go.
Here is a project based on peer-to-peer concepts that aims to preserve information over long periods of time without depending on specific media, readers, etc.
Seems far more realistic, after all this is what most of us do with valuable data, we copy it from hard disk to hard disk over time.
Ceci n'est pas une signature
Yes. It is a pretty stable medium, but it's not perfect.
I have a pack of cassettes recorded with old stuff I wrote for a C64, 20-odd years ago, and even ten years ago they were already unreadable.
True, but what quality of tape? Standard C60/C90 stuff? The DV tape and format is a bit more robust than that. Also, you specifically mention the C64 - not using a D2CN are you (or was it DC2N?). They were pretty poor even with brand new tapes at a time when C64s were current.
As I say, it's not perfect - better would be the proper archival Exabyte stuff. It's better than nothing however.
But magnetic tapes do not strike me as particularly stable. Hard disks may be more stable than tapes.
I would have agreed with you about three or four years ago. However, I'm increasingly nervous of these the quality on these new high speed big disks, and you can see the warranty period dropping through the floor. Perhaps I'm being a luddite, but I don't trust them for long-term storage.
A tangential point is that you're always tempted to start using a hard drive for something else. "I'll just repartion and throw a distro on there". "Hmm...nowhere to put the data files from this app, I'll use the big disk"...that kind of thing. For archiving (as opposed to merely backup), the harder it is to modify the media the happier I am.
Cheers,
Ian
eg: Five year refresh cycle (ie: every five years, you start from the beginning of your data collection and refresh it all). Eventually, you reach the point where the refresh takes five years and one day...
And acid free paper doesn't turn to ash.
The RIAA must be ROTFLTAO at the thought that the plastic they sell is a perishable good. Only slightly (take the long view, some books are hundreds of years old,) more perishable that the original source which only lasts as long as an echo.
I have vinyl from the '60s and '70s that I played on a good turntable then and (since I still have that turn table,) I can still listen to now.
Since the early 20th century, our industrial processes have been destroying our heritage.
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
Considering the relatively short life expectancy of digital media, the DMCA, and the extensions to copyright term over the past few decades, imagine the Dark Age our children and grandchildren will be facing 50-100 years from now. Only the memories of old men and women and the loot of "pirates" will be available to help fill in the great blank space in our cultural history.
In the big picture, who cares that a book lasts for centuries. I care that the information lasts for ever.
Keep the data on live networked file systems and have a maintenance process.
- When drives go bad replace them
- Keep short term backups incase of catastrophic or human failures
- keep hardware up to date
The data from my file systems circa 1991 are still alive, because I continue to keep multiple copies on networks so it is easy to "rsync".
(The 20 MB drive I was using in 1991 is dead by the way, so is the machine, its predicessor, and its predicessor. The next two are still alive, but not my primary machine. See, I have migrated my data with the technology.)
Joe
Joe Batt Solid Design
Wow! I wonder if I can get one of these for my wine cellar.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
What good is archival quality media, if you don't have the device to read it with?
Un-news
I think it's even more hideous with the advent of digital cameras. How many people in this world are keeping their children's memories on a disc because it's cheaper than standard film or cheaper than printing out the digital photos? How many people will find out in 10 years that they have zero pictures of the children as babies? As a parent, that's a a very scary thought.
With that said, I always thought DVD-R for Authoring were supposed to be the big bad media that was made for archiving data. Granted that's not a CD-R, but I was under the impression that at least some optical format existed for "consumer" use (it's pretty expensive for the drives right now). Anyone well versed with optical media care to comment?
Also, I have compact discs that are pushing 15 years old that play just fine in my car, computer and home CD player. Is it not possible to make this kind of durable media available to the public?
When I read the previous slashdot post about CDRs rapidly decaying (even becoming unreadable in a few years) I had trouble believing this... but I ran my own tests using the "Nero CD Speed" tool's ScanDisc option.
What I found was that my 3 to 4 year old archival CDs had anywhere between 20% to 50% of their surface damaged; they had (recoverable) errors. This spanned multiple brands, including Memorex, Acer, and HP.
Remember that data correction algorithms can recover from minor errors, but if data is becoming damaged this quickly it will be not too long before data is actually lost on CDRs.
Is there any reason you couldn't design a "book" that would actaully be a machine-readable optically scanned card deck. You'd get the advantages of a durable paper stock, and the decks could be bound in such a way that they could be mechnically unbound, read, and returned in the way similar to a tape library.
I'm not sure what kind of data density you could get, though, although I suspect it would be slightly more than you might think. It creates a storage problem, but then it has great durability, and the machine to read it would arguably be easier to re-make in the future than the ones used to read traditional optical media, since you could include a card in each deck explaining in human terms how the deck is encoded.
I think P2P would make the ultimate archival solution. You get several machines dedicated to storing your archival data in different places throughout the world, then share all the data from those machines with everyone else. With everyone duplicating data it will be more resistant to loss.
My oldest CD-R is from 7 Oct 1996. I just copied its entire contents to my hard drive without encountering any errors, so it *appears* to be entirely readable. The CD-R is a Verbatim "DataLifePlus" CD-R, and it is dark blue. The contents were burnt at 1x speed. The contents are only 250 Mbytes, so it is not close to full.