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Most Digital Content Not Stable

Zonk posted about 7 years ago | from the define-stable dept.

The Internet 353

brunes69 writes "The CBC is running an article profiling the problems with archiving digital data in New Brunswick's provincial archives. Quote from the story: 'I've had audio tape come into the archives, for example, that had been submerged in water in floods and the tape was so swollen it went off the reel, and yet we were able to recover that. We were able to take that off and dry it out and play it back. If a CD had one-tenth of one per cent of the damage on one of those reels, it wouldn't play, period. The whole thing would be corrupted'. Given the difficulties with preserving digital data, is it really the medium we should be using for archival purposes?"

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That's nothing, think of DRM (4, Insightful)

iamacat (583406) | about 7 years ago | (#18416771)

That content can not be preserved at all. We'll be a civilization without written history, like American Indians.

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

Rude Turnip (49495) | about 7 years ago | (#18416987)

And if they didn't insist on DRM in their smoke signals, they might still be a pretty formidable group today.

Re:That's nothing, think of DRM (0)

Anonymous Coward | about 7 years ago | (#18417427)

How does that foot taste?

Re:That's nothing, think of DRM (1, Insightful)

maxume (22995) | about 7 years ago | (#18417011)

Depending on how you define 'American', you can thank the kind missionaries that told many of them they needed to burn their written histories.

Re:That's nothing, think of DRM (0, Offtopic)

evil_Tak (964978) | about 7 years ago | (#18417121)

Most groups of Native Americans didn't have writing, let alone written histories.

Re:That's nothing, think of DRM (1)

maxume (22995) | about 7 years ago | (#18417293)

We should be sure to lump the ones that did in as ones that didn't.

Re:That's nothing, think of DRM (1)

iamacat (583406) | about 7 years ago | (#18417145)

While whites did enough evil, like stealing the whole country, American Indian writing systems were actually developed by missionaries.

Re:That's nothing, think of DRM (2, Informative)

saforrest (184929) | about 7 years ago | (#18417227)

While whites did enough evil, like stealing the whole country, American Indian writing systems were actually developed by missionaries.

I think that was the point behind "depending on how you define American" -- the GP was referring to the urbanized cultures of Mexico, Central and South America that had writing systems that they were forced to give up along with the rest of their culture.

Re:That's nothing, think of DRM (-1, Flamebait)

Anonymous Coward | about 7 years ago | (#18417455)

If by forced you mean they lost the war then yes, they were forced. If somebody tried to claim your land would you ever stop fighting. I know I would stop when i was dead. They were just pussies. If they had any conviction we woudl be at war with them today.

Re:That's nothing, think of DRM (3, Insightful)

MBGMorden (803437) | about 7 years ago | (#18417623)

[quote]While whites did enough evil, like stealing the whole country[/quote]

Well, I'm 1/8th Native American (but 7/8ths White) if that counts for anything, but this is always overblown. Whites/europeans came in and conquered the land. That's what people have done throughout all of recorded history. The Romans Conquered the Greeks, the Normans conquered the Saxons, etc. The list goes on and on. The case has ALWAYS been that if some other nation wanted your land and you couldn't stand up to them in a military confrontation, then you were gonna loose that land.

Now I'm not saying that it's right or justified or anything, but European conquest into North America is always vilified much more than any other tale of conquest, and I'm not sure why.

Re:That's nothing, think of DRM (0)

Anonymous Coward | about 7 years ago | (#18417467)

Well, realistically it always gets cracked, the only effective protection DRM puts on anything is legal - you're not "allowed" to crack it. it will be interesting to see if that remains true for content after it gets released into the public domain.

Re:That's nothing, think of DRM (0)

Anonymous Coward | about 7 years ago | (#18417547)

Some of the more organized American Indians did have written history: the Mayans. They developed a calendar system (accurate to about 26,000 years), a mathematics system that included the concept of Zero, and thousands of manuscripts. Sadly only 4 manuscripts are known to exist today the rest were burned by Europeans trying to convert the natives to Christianity. We don't have written history of these people NOT because their written history could not be preserved but because of the ignorance of people who destroyed this history.

Multiple identical copies? (4, Insightful)

WinterSolstice (223271) | about 7 years ago | (#18416781)

Isn't that the point of digital? Lossless copies are possible (depending on format obviously). Why have one plastic cylinder that can be lost when you can have it in 5 or 10 locations?

Re:Multiple identical copies? (5, Informative)

t00le (136364) | about 7 years ago | (#18416877)

Any good backup strategy will have multiple media types, so CD/DVD should not be your primary backup media type. If you prefer to have an medium for fast access, then it is still viable. As long as it is not your primary media type, which should be something with tried-and-true longevity.

Like what? (1)

remmelt (837671) | about 7 years ago | (#18416941)

The point is: Like what?

Re:Like what? (2, Informative)

t00le (136364) | about 7 years ago | (#18417083)



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

Re:Like what? (0)

Anonymous Coward | about 7 years ago | (#18417655)

Sonny, DVD is the greatest thing in the world. Except for a nice DLT, a data, lettuce and tomato sandwich, where the data is nice and lean and the tomato is ripe. They're so perky, I love that.

Re:Multiple identical copies? (0)

Anonymous Coward | about 7 years ago | (#18416917)

Exactly: This "problem" has already been solved by (drum roll please) REDUNDANCY.

Re:Multiple identical copies? (4, Funny)

Red Flayer (890720) | about 7 years ago | (#18417615)

So (-1, redundant) should now be (+1, redundant) for posterity's sake? And dupes are posted for archival reasons?

I'm confused.

Re:Multiple identical copies? (1)

Vokkyt (739289) | about 7 years ago | (#18416939)

Exactly; granted, you can kill a DVD, a HD, or a CD relatively easily; however, at the same time, you can archive to all three in a few minutes, whereas making carbon copies of film strips and audio reels takes considerably longer and also is not as easily stored as digital content. On top of that, access becomes an issue; watching 8mm films requires a projector to display them, meaning you have to keep a projector in good working condition while parts and service-workers for the projector vanish as new technology comes. For the time being, CDs, DVDs, and HDs will still have people able to service them and literally millions of machines to access the content with. As technology progresses, if there is a change in the way that data is stored, content will still be fairly easy to transfer over, since the technology will be more readily available than computers were during their advent. (Meaning more people will have access to it to work on converting the data quickly)

Basically, Digital storage is a fine solution, assuming you play to its strong points.

Re:Multiple identical copies? (0)

Anonymous Coward | about 7 years ago | (#18417173)

Errr, you don't *need* a projector to watch a film, only if you want to actually see the motion, but really, to watch an 8mm film strip? Just rig a reel to spin at a user adjustable speed and shine a light through the film. Bam, you can access the film strip. Now, I expect to see the complete source to a 9-track tape de-archiver on my desk NOW!

Re:Multiple identical copies? (1)

ShieldW0lf (601553) | about 7 years ago | (#18417351)

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

Re:Multiple identical copies? (2, Insightful)

Hoi Polloi (522990) | about 7 years ago | (#18417445)

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

Re:Multiple identical copies? (3, Funny)

eno2001 (527078) | about 7 years ago | (#18417533)

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

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

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

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

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

Every Superman has his Kryptonite (4, Insightful)

elrous0 (869638) | about 7 years ago | (#18416969)

Yes, analog tape is durable. But let's take it and that "CD" and put them in front of a large electromagnet and see how each fares.

Re:Every Superman has his Kryptonite (1)

MrShaggy (683273) | about 7 years ago | (#18417211)

Unless of course you let the face of the cd hit the piece of metal. then it gets scratched.

Re:Every Superman has his Kryptonite (1)

Grishnakh (216268) | about 7 years ago | (#18417465)

If the data on the CD is particularly valuable, the face of the CD can be polished to remove the scratches, as long as they're not too deep. There's commercial machines which do this, and there's online services that you can send your CDs to to have this done at a reasonable price (less than the cost of a music CD each).

Precisely (2, Insightful)

Sycraft-fu (314770) | about 7 years ago | (#18417067)

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

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

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

So the parent is completely correct. Because of digital's ability to be perfectly copied, and especially with the Internet's ability to distribute those copies to anywhere in the world, it can have a permanence far above and beyond analogue. The individual copies might be fragile, but get a few thousand, or million of them and you'll be hard pressed to get rid of them all.

Re:Precisely (1)

drinkypoo (153816) | about 7 years ago | (#18417197)

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

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

Hobbyists alone are sufficient to maintain the means to read old data formats, and some of them will be easily readable by other means in the future anyway. For one prime example, you can read punch cards by scanning them and doing image analysis - but of course, you don't have to, because some hobbyist geek has a reader for basically any kind of punch card you can come up with.

Re:Precisely (1)

WinterSolstice (223271) | about 7 years ago | (#18417241)

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

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

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

Re:Precisely (2, Interesting)

skoaldipper (752281) | about 7 years ago | (#18417281)

Here's [computerworld.com] an alternate article which might shed some light:

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

1. Even if a 1000 backups are made today, unless each successive backup (say) 2-5 years from now includes _all_ the information from today, those original 1000 backups are quite useless.

2. Having been a victim of HD fluid bearing loss (from a brand new Maxtor drive only lasting 16 months), even HD(s) aren't reliable.

3. As long as item 1 is handled by ever increasing storage capacities, it's not an issue. However, redundancy doesn't stop at 2 (hd -> CD). It's better to have a long term solution like magnetic tapes (or other) imo.

It's already happened/happening. (4, Insightful)

Kadin2048 (468275) | about 7 years ago | (#18417503)

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

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

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

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

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

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

Re:Precisely (1)

clickclickdrone (964164) | about 7 years ago | (#18417601)

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

Re:Multiple identical copies? (4, Insightful)

gad_zuki! (70830) | about 7 years ago | (#18417187)

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

Also I'm certain for every analog horror story there is a digital lucky story (and vice versa). Not to mention digital encodings usually have some kind of redundancy. A small scrach does nothing but the same scratch on an lp forever destroys some part of the track. I wont even go into the magic of data restoration (which the author ignores). There's really no 'tough medium for the ages' out there that can do it all. Just complaints and blind-luck stories.

LOCKSS (was Re:Multiple identical copies?) (1)

DenialS (21305) | about 7 years ago | (#18417593)

Yep. Librarians and archivists aren't stupid -- that's why we have invented digital replication systems like Lots of Copies Keep Stuff Safe [lockss.org]. From the site:

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

People with responsibility for scholarly assets agree: digital preservation is important. With your help, librarians and publishers are asking two fundamental questions: From this moment on, who will have custody of societies' electronic information? From this moment on, who will control and govern societies' electronic archival assets?

Join us! The community is working to insure important scholarly assets remain available in a distributed, self-repairing, robust, digital preservation system.

LOCKSS is OAIS compliant, LOCKSS migrates content forward in time, and LOCKSS continually audits and repairs the content. LOCKSS is open source software -- the system is freely available for you to examine and use.
We understand the importance of preserving cultural memory. LOCKSS is one way that we can cooperatively protect digital collections from physical calamity, abandoned formats, economic hardship, changing political climates...

Stone tablets (5, Funny)

IckySplat (218140) | about 7 years ago | (#18416785)

Stone tablets. Just drill a hole for a zero and your away and laughing
Now we just need a large enough area to store them :)

Re:Stone tablets (1)

gardyloo (512791) | about 7 years ago | (#18417007)

Stone tablets. Just drill a hole for a zero and your away and laughing
And make a scratch for an apostrophe and e!

Re:Stone tablets (2, Insightful)

NewWorldDan (899800) | about 7 years ago | (#18417299)

Rather glib, but a very important point. The biggest problem is data density. The higher the data density, the less damage it takes to destroy it. The other upside to digital data is the ability to build in fault tolerance. CDs, for example, are fault tolerant. They can accomodate a certain number of scratches and bad blocks and still produce 100% accurate output. On the other hand, this tolerance comes at the expense of (wait for it) data density. The upside to analog data, is that damage distorts without destroying.

Re:Stone tablets (1)

IckySplat (218140) | about 7 years ago | (#18417573)


But just think of the poor bastard who's job it is to transcode
Wham's greatest hits to Stone tablets armed with nothing but a BIG
pile of stone tables and a drill press :)

Re:Stone tablets (0)

Anonymous Coward | about 7 years ago | (#18417589)

The upside to analog data, is that damage distorts without destroying.

An advantage that comes at the expense of (wait for it) data density.

No. (0, Flamebait)

JayJay.br (206867) | about 7 years ago | (#18416805)

If you are using CDs, or for that matter DVDs, for archival, you deserve it.

PS: Not flamebait. Anybody who has worked seriously on backups/archiving knows for sure that magnetic is still the way to go.

At least for now.

Re:No. (1)

Overzeetop (214511) | about 7 years ago | (#18416991)

Absolutely. Tape backups never drop bits - and nobody has ever had a tape go bad - as we all know. Except maybe that $38B thing in Alaska.

Re:No. (1, Interesting)

Anonymous Coward | about 7 years ago | (#18417095)

Yup, DDS tapes renewed every 5-7 years is the only way to go.

Tape, whether analog or digital, usually suffers "bleed through" effects after about 7 years.

Of course, CD and DVD are disposable, temporary media, though their durability depends a lot on the quality (price) of the media.

I guess Denis Noel is not an archivist after all, despite being hired as one. Government has a knack for hiring the lest competent people possible. I suspect it is a strategy as the less a government actually achieves, the smaller the political risk and the greater the chances of re-election. Don't you just love democracy?

Re:No. (1)

rudeboy1 (516023) | about 7 years ago | (#18417155)

I concur. The question the submitter asked in point of fact, should have been titled about optical content, not digital. Digital content is fine. Storing sensitive data on tape is as far as I am aware, still the industry standard. Storing sensitive data on DVD or CD is just a bad idea, unless you are looking to have a backup of the backup sitting next to your office computer for easy reference. A disc should never be a primary backup.
    Also, you need to find another archiving company if you are getting tapes back that have been subject flooding. Additionaly, most of this argument is moot, since every major IT department I have ever worked with makes backups that are rotated regularly. In the event of older data that must be archived indefinitely, I believe tapes still have the edge on untouched longevity. I.e.- A tape and a DVD are sitting next to each other (in their respective protective casings) in a vault. Absent of a fire or an EMP, I believe I am correct in that the data will survive longer on the tape than on the DVD.
    A lot of archiving companies do all of this as their standard practice, making you not liable in the event of a problem. Blue Mountain seems to be the gold standard around here. Are they a national company, or do they only do the midwest?

oh, just (2, Interesting)

superwiz (655733) | about 7 years ago | (#18416817)

let's play it all by memory. Seriosly, do we really have a choice? The more densely we pack the information that more of a chance it has for corruption. The "CD" mentioned by the article has effectively 700 minutes of music of the same quality as the 60 minute tape.

Re:oh, just (0)

Anonymous Coward | about 7 years ago | (#18416919)

Err, don't CD's still have 80 minutes of music (Lossless that is, or relatively so depending on the ADC used in the recording, MP3's are very lossy).

LAME vs. cassette? (1)

tepples (727027) | about 7 years ago | (#18417183)

Err, don't CD's still have 80 minutes of music (Lossless that is, or relatively so depending on the ADC used in the recording, MP3's are very lossy).
Are LAME and Vorbis at 128 kbps ABR lossier than a typical cassette [wikipedia.org]?

Re:LAME vs. cassette? (0)

Anonymous Coward | about 7 years ago | (#18417383)

Well, Cassettes are crap, no argument about that, but how many consumer CD players can play an Ogg Vorbis formatted CD? Also, yes LAME is just MP3 encoding, right? By design MP3 is lossy, since it eliminates data which is not perceived as important by humans, but it's still missing from the final product.

Contents isn't supposed to be stable (1)

grahamsz (150076) | about 7 years ago | (#18416819)

I like that digital content is fluid and can be easily changed.

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

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

Re:Contents isn't supposed to be stable (1)

AJWM (19027) | about 7 years ago | (#18417103)

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

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

There are other film types -- and the stuff they use (used to use?) for microfiche is rated in centuries if kept in climate-controlled conditions. Under hot and humid conditions, though, fungus can attack the binder for the silver halide. (The diazo-based fiches only have a nominal 20-year life, although I've got some older than that which are fine.)

3.5" (4, Funny)

otacon (445694) | about 7 years ago | (#18416825)

At the enterprise level we use 3.5" 1.44MB Floppy drives in an elaborate redundant array. It consists of roughly 70,000 Disks, each changed nightly. We haven't had any problems yet. Hopefully the rest of the world will play catch up soon.

Re:3.5" (-1, Offtopic)

Anonymous Coward | about 7 years ago | (#18416957)

I'm frightened beyond description that this isn't tagged as funny.

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

Anonymous Coward | about 7 years ago | (#18416827)

Ridiculous. It's not the fact that content is digital, it's the fact that the media being used to store the information (CDs etc) is fragile. If these mythical audio tapes had been digital tapes, recovering the signal from them would have been just as easy.

Re:It's the messanger, not the message (0)

Anonymous Coward | about 7 years ago | (#18417061)

If these mythical audio tapes had been digital tapes, recovering the signal from them would have been just as easy.

Not at all. Those audio tapes were analog, if 30% of their data was lost you could still make the recording out pretty well, if only 30% remained you could still tell what was going on. A digital tape, if 10% of the data is gone its likely unrecoverable (assuming the 10% is randomly lost). Simple digitations, like old school Laserdiscs and CD's, there's still a lot of redundnacy in the date, it might be better off, but most digital content is also compressed making every bit far more important.

Re:It's the messanger, not the message (1)

wolff000 (447340) | about 7 years ago | (#18417085)

Absolutely right. Nothing is wrong with digital it all depends on the medium. I have seen hard drives take a beating but after sending them to a clean lab to have the platters put in a fresh case everything was recovered. Yes it costs a ton but holds up well over the years and even with some severe damage can be recovered. Also as already stated by those before me, if you use just cd/dvd for archiving you are asking for it. Even my personal pc is backed up to 3 different sources. An external hard drive, dvd, and magnetic tape. The external hard drive doesn't even live at my place it is stored at a friends in a different state. No natural disaster barring something that wipes out half the US is going to make me lose a single byte of data. If I as a loan individual go this far why isn't every company on the planet? It would be a pain for me to lose files but wouldn't destroy my financial lively hood vs a company that depends on the data for survival.

Re:It's the messanger, not the message (0)

Anonymous Coward | about 7 years ago | (#18417141)

Thank God it's the messanger and not the message, because something might have been lost in translation!

First post? (-1, Offtopic)

Anonymous Coward | about 7 years ago | (#18416833)

Id yell it, but Im now scared it will be damaged, perhaps I should send a letter?

But what you got off the tape... (4, Insightful)

dave420 (699308) | about 7 years ago | (#18416839)

... wasn't *exactly* what you put on. You have the appearance of stability, that you can retrieve something off a damaged tape, but the truth is something different. That's the beauty of analogue. The same simplicity and fault-tolerance of the format also means the format will naturally degrade over time. The contents may be retrievable, but they've degraded, and as such are not the same contents as when first written. Digital fails, but when it doesn't fail, you have exactly the same content as you did when you started. Archivists will not run from digital - their techniques will improve instead. or something.

Re:But what you got off the tape... (0)

Anonymous Coward | about 7 years ago | (#18417497)

Digital copies fail, but in blocks. With multiple copies, a complete, accurate copy can often be constructed from the parts since they would not generally fail in the same regions.

First (2, Interesting)

WormholeFiend (674934) | about 7 years ago | (#18416841)

we need to realise that nothing lasts forever.

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

Re:First (1)

VE3MTM (635378) | about 7 years ago | (#18416955)

we need to realise that nothing lasts forever

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

Re:First (1)

jusDfaqs (997794) | about 7 years ago | (#18417077)

Hey go to the mail store temple for last year and read me the glyphs for the user Tut.K please. I don't know where they are probably on one of the back walls somewhere, maybe we used a pillar for extra space was a busy year...........

Re:First (0)

Anonymous Coward | about 7 years ago | (#18417107)

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

Why, yes. Many of our creations still exist today.

This is why we still hear Ethel Merman and Wham! played now and again.

Crush and Preserve! (3, Funny)

webword (82711) | about 7 years ago | (#18416871)

Shouldn't it be possible to take all the media and just crush it? You know, like throw it into a Mega Power 3000 Digital Garbage Collector (TM) and crush it into a diamond or something? Let future generations figure out how to decompress it.

wring recovery method (4, Informative)

Red Flayer (890720) | about 7 years ago | (#18416905)

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

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

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

Re:wring recovery method (4, Informative)

Criffer (842645) | about 7 years ago | (#18417129)

Exactly. If you try to put a bent CD into a CD drive, you're obviously not going to be able to read it. But that doesn't mean its not recoverable.

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

The result is a CIRC that can completely correct error bursts up to 4000 bits, or about 2.5 mm on the disc surface. This code is so strong that most CD playback errors are almost certainly caused by tracking errors that cause the laser to jump track, not by uncorrectable error bursts

They could try harder (4, Interesting)

Waffle Iron (339739) | about 7 years ago | (#18416913)

The CD wouldn't play with an off-the-shelf CD player. That doesn't mean that a special "archaeological" CD player can't be built that would perform extensive microscopic image analysis of the disk surface in order to read the data in the face of extensive corruption.

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

Re:They could try harder (2, Informative)

clickclickdrone (964164) | about 7 years ago | (#18417459)

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

Re: (0)

Anonymous Coward | about 7 years ago | (#18417003)

Your audio tape surely has lost some bits during its water accident. Though you may be able to play it, it is like you have downsampled the bitrate of an mp3. Oh, _that said_, even if my (S)VCD is borked at one spot, I can (usually) still play it, with a little video glitch of course, just like your audio tape. The problem is that most CD/DVD drives retry too long on one sector, even at the hardware level.

have people already forgotten? (4, Informative)

phantomfive (622387) | about 7 years ago | (#18417029)

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

Re:have people already forgotten? (1, Insightful)

jbossvi (946552) | about 7 years ago | (#18417525)

What are you talking about? backup tapes are digital bits represented as analog signals xfer'd onto a magnetic tape. So when you read the analog signal back it transforms given the signal into a digital bit. To make a copy of a DLT tape it will get converted back to digital-copied-xfer'd to tape exactly as the original.. you can copy this backup media millions of times without loss of bits... you must be thinking of plain old audio analog tapes where every analog-analog copy got worse.. really if what you are saying is true, backup tapes would be pretty useless.. dont know how you got modded +4 informative

600MB on audio tape? (1)

Mirar (264502) | about 7 years ago | (#18417041)

...so you can store 600MB on an audio tape now? ...can you recover a backup tape that can store any significant amount of data using the same methods?
If not, what's the point of comparison?

But in fairness, how does the write-once flash memory that Sandisk announced stand in comparison to the audio tape? Or a normal HDD?

1% = Total Loss? (3, Interesting)

JesseL (107722) | about 7 years ago | (#18417057)

If losing 1% of the data on a CD means the data is a total loss, doesn't that say to you that you should be using a file system and data formats with more redundancy and parity?

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

Re:1% = Total Loss? (1)

clickclickdrone (964164) | about 7 years ago | (#18417509)

There's a tool whose name escapes me (useful huh?) that generates checksums for a DVD or CD and claims (I haven't tried it) to be able to recover a disk even whan large chunks are damaged.

Re:1% = Total Loss? (0)

Anonymous Coward | about 7 years ago | (#18417621)

and then someone destroys the ozone layer, and all the information is gone!

Apples and Oranges (2, Informative)

Overzeetop (214511) | about 7 years ago | (#18417133)

The tape had analog data on it. Analog, as we all know from years of television and radio, is very forgiving of damage. CDs are digital data. There is error correction, but for normal playback/reading devices there is a limit beyond which they simply give up trying. The data is perfect or its gone for those machines.

Sad to say, tape dies too.

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

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

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

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

density versus longevity (0)

Anonymous Coward | about 7 years ago | (#18417165)

In their quest to cram more bits onto the media, they've sacrificed longevity.

We could have very robust backup media, but it wouldn't have the density of a DVD or DLT.

They still use mylar paper tape for sequencing machine tools, it's super low density, but name another media that will survive exposure to metal shavings and coolant.

I've said it before and I'll say it again... (3, Funny)

eno2001 (527078) | about 7 years ago | (#18417167)

...the solution is simple. We need a way to take a quantum snapshot of the whole of the Earth at least once every 24 hours and then to send that data out into space as a broadcast in all directions. To retrieve the quantum structure, we'd simply pop out of a wormhole near where the data is passing and retrieve it, then retransmit it back to here and reconstruct the Earth as it was before catastrophe struck. The nice thing about this is that if we can find another M class star like Usolia (our sun), we don't even have to beam the data through the wormhole. We could just intercept it near the star and start the assembly process there. Point-in-time restores for the whole of the planet. Imagine that. You're welcome.

It's all about redundancy (0)

Anonymous Coward | about 7 years ago | (#18417193)

With digital data, we have a vastly better chance of protecting data from disasters - and never use it. The data on a CD is not recoverable if 50% of the disc is unreadable, because there's not that much redundancy. Audio tape is recoverable under extreme circumstances because there's much more redundancy: The storage density is lower because the individual bit of information is stored in a much bigger (and thus harder to destroy completely) area. You can do the same with digital data. Just spread the information so that it becomes very unlikely that a disaster destroys every place one bit is stored. Error correction codes can be used to make this much more effective and efficient than keeping plain duplicates or simply lowering the storage density, which are the only two options you have with analog media. We're just so stuck in the belief that digital makes everything smaller that we tend not to "waste" storage space on redundancy. When was the last time you made an off-site backup?

Remember the "Domesday Book" (3, Interesting)

hopbine (618442) | about 7 years ago | (#18417245)

In the 1980's they digitized the Domesday Book. Trouble was the format they used is now obsololete. The good news (apart from still having the origional) they have re-inveted the wheel. http://news.bbc.co.uk/2/hi/technology/2534391.stm [bbc.co.uk] for details.

Re:Remember the "Domesday Book" (1)

porkThreeWays (895269) | about 7 years ago | (#18417609)

Things like this frustrate me. I'm the last one at my workplace still using a system as simple as tar and gzip. But you know what? I'll be the only one that will be able to easily read my archived data in 5 years. We get these companies like HP coming in and trying to sell us extremely fragile technology and I just have to laugh. What is the point of a backup that lasts 100 years if you don't have the resources to read it. When it comes to archives and backups, simple is better. Human readable plaintext where possible, timeless standardized documented formats, and simple hardware you think you can store for a very long time. Not expensive fragile tape libraries that "eat" your data and you can only hope it will consistently throw it up.

Some might consider it an advantage. (0)

Anonymous Coward | about 7 years ago | (#18417265)

Stable media can hang around for a long time. Media like film, paper, stone also have the annoying property that the information can usually be recovered without resorting to rebuilding the machines to read the media. That means almost anyone could view the information!

Look at all the trouble the Constitution and Bill of Rights have caused! If they were stored instead on a medium requiring proprietary devices (now lost to time) to read the masses would never know exactly what they said. All that time wasted by congress and the courts could have been saved!

Who needs a cultural history anyways, its not like controlling the past has any sort of advantage; we've always been at war with Eurasia, that's all we need to know.

Umm.. (4, Insightful)

phasm42 (588479) | about 7 years ago | (#18417287)

If a CD had been submerged in water, it would've been fine. There's no point in making the comparison if it wouldn't have been damaged in the first place. They need to find a better example.

Mission-critical archives and backups (2, Insightful)

zuki (845560) | about 7 years ago | (#18417335)

There is much that has already been documented and guidelines exist [cdpheritage.org] to guarantee somehow the short to medium-term preservation of digital assets; this particular link is for audio-related digital assets, but data is all the same...!

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

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

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


I use hard drives. (0)

Anonymous Coward | about 7 years ago | (#18417399)

I currently have two 320GB external USB drives with everything I consider important on them. Once a week I update each copy, and they are both stored in completely different physical locations. Every couple of years or when the technology changes enough, I buy a bigger/newer drive and copy everything over. I intend to do this until the singularity comes and it all becomes moot.

Can anybody say... (1)

whtmarker (1060730) | about 7 years ago | (#18417409)

Thats funny, Google or Yahoo has never lost my entire email account due to 'Digital Content Not Stable'.

RAID 6 eh? [wikipedia.org] (not to be confused with raid 6a).

Here's how to make your digital backups.... (1)

Lord Bitman (95493) | about 7 years ago | (#18417449)

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

use error correction! (0)

Anonymous Coward | about 7 years ago | (#18417499)

You don't have to store everything in the native format (like red book). You can
take advantage of error correction codes and put a lot of redundant info on there. To the point
that you'd have to damage a large percentage of it to really screw it up.

Sorry to spoil the fun (VXA tape format) (2, Informative)

mihalis (28146) | about 7 years ago | (#18417543)

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

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

So You've Lost a $38 Billion File (2, Insightful)

jeevesbond (1066726) | about 7 years ago | (#18417569)

Chappies in New Brunswick:

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

From an earlier /. article:

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

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

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

Incompetent archivist alert. (1)

RealProgrammer (723725) | about 7 years ago | (#18417597)

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

Sometimes I've not been able to recover disks that have been damaged beyond a certain point. But I've never lost a CD because it got wet, or had one become unplayable because it warped. I keep backup tapes in a water-resistant container (or in a bank vault).

And with digital media, as others have noted, I'm not limited to one archival copy.

DRM is a red herring, as encrypting archive copies of sensitive material is a feature of digital media, not a flaw. DRM is only tangentially related to media stability, since any encryption you would use to protect archives would be have high fault tolerance and recovery. And if you've done your job and made duplicates of anything you'd get fired for losing, having an encrypted backup be damaged is no different than having an unencrypted one damaged. Either way, DRM on backups doesn't matter for recoverability.

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