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Digital Storage To Survive a 25-Year Dirt Nap?
AlHunt writes "I've been tasked with finding a way to bury digitally stored photographs in a small underground time capsule to be opened in 25 years. It looks like we'll be using a steel vessel, welded closed. I've thought of CDs, DVDs, a hard drive, or a thumb drive — but they all have drawbacks, not the least of which is outdated technology 25 years from now. Maybe I'll put a CD and a CD-ROM drive in the capsule and hope that the IDE interface is still around in 25 years? Ideas and feedback will be appreciated."
Change up IDE for SATA and you might have a chance, since SATA is relatively new and SATA2 is backwards compatible with SATA1, etc.
Seriously, just print them. Unless we somehow evolve new sensory organs in the next 25 years, I suspect that photographs won't be rendered useless through obsolescence. They can always scan them into new digital files afterwards.
How about a small digital picture frame? That way you could throw in your own flash drive, and the pictures would come with their own display medium. I'm sure they'll still have AA batteries 25 years from now.
just bury the entire PC. Surely AC power will still be around in 25 years.
You can't guarantee that the data will be intact when they open the capsule. Nor can you guarantee that the gear you send will survive.
Seems to me that your best bet is three separate distribution mechanism.
1. CDs AND DVDs (two copies of everything), a small portable DVD player with multiple interfaces - component/composite/s-video out
2. NAS device with at least two disks (two copies of everything) and multiple interfaces - eSATA/SCSI/USB2/FireWire/ethernet(dhcp)/etc.
3. Digital picture frame and a handful of memory modules (two copies of everything)
Ensure that whatever device you send goes complete with power adapter and user manual. In at least two languages.
All there is to do when you're done, is cross your fingers and hope that video displays still operate in two dimensions :)
It really doesn't matter. If you use any popular media the technology will still be around to use it. We live in a big world, and there always geeks who love to collect stuff like that.
Of all the interfaces that will still be around 25 years from now USB has the best chance. I am not so sure about wether or not the flash memory will hold up. But with the BILLIONS of usb devices out there nowadays I find it hard to believe the format will be gone 25 years from now.
If it absolutely, positively has to survive 25 years, it might be worth the expense of getting the photos professionally printed on good quality paper and, if you're worried about the box leaking, laminated. Okay, it's a smartass answer, but those are photos you're going to store, and they're known to last more than 25 years easily.
No kidding!!! What do you say at this point?
Screw digital. Get them printed to archival-grade microfilm and store them in a moisture-proof container. Microfilm is designed to last a minimum of 500 years when kept under the proper (and relatively easy to maintain) condition. All you need is a light source and a good lens to view it. Most of the world's better professional archives use a combo of microfilms and digital archiving to keep stuff around... the microfilm guarantees longevity while the digital copy is easy to search and access.
The 5.25" optical disc format seems to be the most likely to survive, given that the CD doesn't seem to be getting replaced in a physical format anytime soon, and the follow-on products (DVD, HD-DVD, Blu-Ray) all use the same basic format and are backward-compatible due to the low cost of the lasers involved for the previous format(s). Given the preference in the mainstream to keep backward compatibility and the fact that even the fun new terabyte media are in a similar format, this is the best overall bet.
You can never go home again... but I guess you can shop there.
Alternative title: "How many bullshit redundant replies can you fit in a Slashdot thread?"
If you use paper, SD card, USB memory stick, hard drive, or whatnot it would have to survive being welded into the box, as well as opening the box.
If I have nothing to hide, don't search me
It would be entirely possible to make a paper copy of binary data that could easily be read in with the correct software. Of course, the paper you would want to use would be acid-free.
One could simply encode the binary as forward slashes and backward slashes. Or as x's and o's.
But those would be really wasteful.
I've often thought that what would make a really good software contest would be to develop a format to back data up to a paper copy on a laser printer using the best compression possible but with enough error correction and detection to be able to read just about any paper put in that comes out in reasonable shape.
For example, one might use individual pixels on the paper. Or you might want to group several together and treat as a bit. Or use an innovative coding scheme that doesn't just map individual bits to spots on the paper.
I think that a scheme that spreads the information out over the entire paper might be interesting. In other words, the individual bits of a byte and any bits dealing with the error detection and correction would be located remotely from each other.
In such a contest, testing would be easy. Write images of several datasets to paper and then scan the images in after different stages of intentional damage to the paper. For example, you might read two data files back from the pristine paper without doing anything. Another two data sets might come from paper that has been crumpled up into a ball and then flattened. Two more might be from paper that has been moistened. Two more from paper with a tear across the middle. And, finally, make copies of two data sets on an everyday copier and then scan them in and decode.
Rank the results by the numbers of errors, possibly with factors to take in levels of difficulty based on the amount of damage to the paper, and select a winner.
what format was around 25 years ago, that is still available today?
now- what was around 50 years ago- that is still available today?
now-- for the hell of it, what's been around since 1844--- and still available today?
every day http://en.wikipedia.org/wiki/Special:Random
Electrolytic capacitors are used in the power supply filtering of essentially all circuitry currently in use. These components will be present in a number of places on the circuit boards of both disk drives and memory sticks.
The insulating layer between the plates in electrolytic capacitors is formed by electricity-driven chemical action. It gradually degrades over a period of several years. If the capacitor is operated occasionally the operating voltage across it will rebuild the insulating layer. But if it's left unused for too long the layer will degrade to the point that, when power is finally applied, the capacitor will short and (because most of them are hooked across a power supply) fail catastrophically. Like by blowing open and jetting chemical fumes, while shorting out the supply and damaging other components in the current path.
Mechanical moving parts may lose lubrication and spot-weld with time. This also makes storing entire drives problematic.
Recordible CDs usually record on a die layer that will degrade with time.
Some types of flash memory store data as stored charges, which will leak away with time.
So IMHO degradation of the medium itself is likely to be a killer problem. Much more than readability with future devices. (After only 25 years there should still be some working players available for currently widely-deployed standards, even if no new ones are being manufactured. Once you've go the bits read you can transfer them to new media.)
Things I'd consider:
- Integrated circuit memory devices using a technology like fusible link or a crystalline/amorphous transition. (Replace any electrolytic capacitors with ceramic types - which will greatly increase the size of the assembly.)
- CD masters involving actual removal of material - a material inert enough that it will not corrode away with time.
- If you want to store drives for removable media (and convert the caps), check with the manufacturers about what the bearings are like and talk with a mechanical engineer with applicable experience (like mil-spec or space-rated). I'd avoid sealed hard drives, especially those that don't lift the heads off the platters when parked.
Also: Use a coding scheme that has industrial-grade error correction. B-)
One downside to your task is that, with only a 25-year storage time, you'll probably still be alive to be blamed for failures when they open it. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Generally speaking, you can pull data from media formats (medium) that are 25 years old. If your capsule was to be opened in 50 or 100 years then you'd have a problem, but most media formats that are 25 years old are still readable today. How much effort it would take varies...
If you had a 160/180/320/360KB 5 1/4" floppy disk from 1983, you could even read it by buying an old 5 1/4" drive off eBay, connect it to the same floppy connector that's still in use today, and read the disk directly in Vista. Now, if instead you were trying to read an MFM/RLL hard drive, 8" floppy, magnetic tape, punch card, etc. from that era, then you'd have more of a problem--but it would still be doable.
Also, many companies make specialty products to connect old equipment to new PCs. While I've never seen one, there's probably a company that makes a USB 5 1/4" floppy drive. If push comes-to-shove, you can always buy old equipment to bridge the gap... If I had an MFM/RLL hard drive from 1983, I could always buy an XT or AT from ~1983-1991 (that has an MFM/RLL interface), connect it to a new PC by way of a serial port (well, the new PC will probably have a USB-to-Serial converter) or Ethernet and transfer the data.
Pick a technology that's very well used today and you should be fine reading it 25 years from now. Sure, it'll take some effort & creativity, but it should work. But if you pick a technology that's old by today's standards and you'll have even more trouble reading it in the future...
That being said, I would worry more about the media--whether it will withstand 25 years of isolation, heat expansion/contraction, humidity, etc.
Windows 3.1x calc: 3.11 - 3.10 = 0.00
There is no good reason to put time-capsules underground besides some strange belief that it should be done that way. You're much better putting the contents above-ground inside of a wall, behind a plaque, etc. This way, it is much less likely for there to be water or other sorts of damage that plagues underground storage, you also have a smaller chance of it being lost or forgotten. If secured properly, there should be very minimal risk of tampering.
Let the people of the future figure it out, if they're so smart. If you really want to encourage them, just label everything "porn" and leave it at that.
You see? You see? Your stupid minds! Stupid! Stupid!
At least Seiko produces serial EEPROMs with > 50yrs data retention, and are rated for high temperatures (125 degrees C).
Those max out at 64k, though.
You'd probably want to use some sort of EM shielding (Faraday cage or similar) in addition to ESD protection, and thermal shielding to keep the temperature on the surface of the die below 125C during welding, and also carefully choose your burying location.
But, yeah, storing thousands (the OP didn't actually say thousands of photos, did he?) of pictures would require thousands of 64k (k-bit, I believe!) of ICs. I can only imagine the programming effort involved; special jigs that house & power hundreds of PROMs per batch write...
When I grow up, I want to have Christopher Walken hair.
Printing would be a space issue as well as the varying qualities of print sources, commercial or otherwise. It seems odd that nobody mentioned microfilm though, the libraries and newspapers have been using it for far more than 25 years and would surely be able to retrieve from it in the future. In fact retrieval will probably be even easier with advances in scanning technology. It saves space and could easily be saved in a smaller and more optimum storage container within the capsule to prevent decay.
Why is everyone suggest A format?
Why not store the data on a:
* DVD
* Pile of CDs
* USB drive
* SD card
* xD card
* Hard drive
And a choice few in hard copy.
Seriously... with the price of these things, and the timeframe, surely you can afford to store it on all of these things and put them all in? Plus it'll be fascinating in 25 years time to see how many are still readable... all? None? Some?
Learn all you can from the (arguably) failure of the BBC Domesday Project and build from there.
My advice for a time capsule is:
It's tough but it just might be doable. Again, the keywords are redundancy and simplicity. If the data is important, make two identical time capsules and store them in geographically different areas (different tectonic plates are safest but this is probably overkill :) ). It's important that the copies of the time capsule be identical so data lost from one can be restored from the other.
-- Sig down
everything needs to be sealed well, however. double or triple on some water-tight somethingsomething to be safe,
Or maybe submerging it into mineral oil. Does anyone know if electronics can withstand 25 years submerged into oil ?
Everything will also need to be redundant :
- burned DVD-R/CD-R media may rot. Harddrive may refuse to spin because of chemical aging of the mechanical part, flash memory could fail, etc...
- as much spares as possible. 25 years from now, spare parts will probably be hard to find.
- a couple of SATA and USB drives/readers. Whatever the are the connection 25 years in the future, USB is currently so popular that in the future, we're bound to see adapters, just the we we currently see Serial-2-USB adapter even if serial connector have been phased out for quite some time.
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Come to think of it, printouts of data compressed and printed out as 2D barcode may be the most durable technology.
- extensive experience shows that, under proper conditions, paper can be made survive for even longer than 25 years.
- reading and decoding a 2D barcode doesn't require any technology specific to the current generation of hardware.
- as long as the data is stored in a redundant manner and that it use open and well documented standard with source code available. It would still be accessible by computer 25 years later, even if it requires some programming and/or re-implementation of a long lost standard.
(as a bonus, include documentation of formats printed in clear on paper too)
- choose simpler standards. chance are none of the current open source library processing it will be available in 25 years. the kids will probably have to re-code a reader / decompressor using whatever will be the popular high-level language du jour ( Ruberlython#++ or something similar ). may make a fun science project for them.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
I have family photographs that are over 150 years old that are quite legible without being stored in a hermetically sealed container. They're glass plate Daguerreotypes, but early paper photos almost as old still look fine, too.
"Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
Only a handful of working systems in US including mine.
That's awesome! I have an old wang I would really like to get something from. Do you think I could take my wang out and put it in your system?
> and I know for a fact that CDRs deteriorate after about 10 years.
Some archival media is rated for 100 years. But forget that, just make a gold master and send it out to be commercially duplicated. It isn't THAT exensive, so have a small run of 100 copies made. Sell 90 of them in a fundraiser to recoup the expense of duplication and stick the other ten into a small stainless steel airtight container with an inert gas. Wrap that in some quality insulation to protect it againt the heat when the main capsule gets welded shut. I have heard lots of 25 year old audio compact discs and they sound just fine. But if there is enough bit rot to make recovering data dodgy, well you have nine more still shrinkwrapped copies to try reading any bad blocks from.
The only remaining question is whether equipment to read a Compact Disc will still be available in twenty five years. And the answer is almost certainly. It probably won't be nearly as popular as it is today but the LP is ten years in the grave and you can still buy a new turntable at Sears.
A pressed DVD might be even better because the recorded media is safely between two layers of substrate instead of only protected by the screenprinted label on the top. On the other hand we have enough history with the CD to know beyond any doubt that they survive in readable condition for the required time, even under typical consumer storage conditions.
Democrat delenda est
Just curious - did you work for Sony or Philips? According to wikipedia CDR were first spec'd in 1988, 20 years ago.
Pick a SCSI model hard drive. These things have been around since 1986, which is pretty close to the 25 years time-frame you are trying for. It also should be noted that we can still connect a SCSI-1 device into a modern day SCSI bus, so if someone had dropped a SCSI drive in 1986 into a time capsule that was to be opened up in 2011, there is a VERY good chance that we would be able to read it. This technology isn't going to go away either in the next 25 years. So it would be the method of choice if you are going to use a hard drive.
We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
There are plenty of books out there older than 25 years old... so print out the (binary, hex dump, 1's and 0's) onto paper and store them somewhere where they will survive.
Hell, even that's too tech... engrave the above into stone and make the Long Now Foundation proud.
p.s. Don't mod this funny. I'm not joking. There is no guarantee that any media that plugs into a computer will be easily accessible in 25 years time, but you can damn well guarantee that they will still have scanners, and that their OCR software will have improved since then.
I don't think it will be the medium that will be the problem, it will be the message. Imagine the shock of those viewing it to learn that our generation thought that there weren't WMD in Iraq or that Han Solo shot first. I'd limit the contents of this a few MP3's and photos of the Whitehouse, otherwise your time capsule will last all of 5 minutes after being unearthed before its whisked away to the Ministry of Subversive Materials.
Actually, better forget the MP3s, or you'll be tracked down by the RIAA and sued for 25years of lost song rental income.
Aide-toi, le Ciel t'aidera - Jeanne D'Arc.