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FWIW, CDs are made like that. DVDs are not, so, I think you're.. stretching the truth a bit.

http://electronics.howstuffwor...
https://www.clir.org/pubs/repo...

The constitution was in active service for longer than the Enterprise, but it's no longer in active service. It's been a museum for 100 years.

How much of the an original wooden vessel survives after ten years, thirty years, 100 years is a very interesting question. In the end, you are always looking at a restoration or re-construction.

Wood rots. Hemp rots. Canvas rots.

Rumors had circulated for half a century that the Constellation was not what its promoters claimed it to be, and [Dana] Wegner's report confirmed them. Investigators from the Navy discovered that the supposed Revolutionary War-era frigate in Baltimore Harbor was actually a Civil War era sloop that had been built in Norfolk, Virginia, in 1854. All it shared with the frigate built in Baltimore in the eighteenth century was its name. It resembled a Revolutionary War-era frigate because during early renovations, some of the ship's admirers had "restored" the Constellation to appear to be almost 60 years older than it was; for example, they added a second gun deck and made other alterations. For most of its tenure in Baltimore, the Constellation was living a lie.
[This] distortion of history came at the expense of the Constellation's own very interesting history. It was, for example, the last and largest all sail-powered sloop commissioned by the U.S. Navy, and while it did not engage in a famous sea battle, as did its predecessor, it did work to interdict the slave trade during the mid-1800s.

Archival Authenticity in a Digital Age

You are correct about federal law. State copyright law is a very different kettle of snapping turtles with regards to audio copyrights. Due to weirdness in the way federal copyright law is constructed, audio recordings made before 1972 are not covered, and so federal copyright law does not preempt state law, and so audio works made prior to then are covered by state common law copyright. In most states, this affords protection until 2049. Some states passed anti-copying and other laws, making it a huge minefield to figure out what the exact legal status is.

There's an excellent paper explaining this available, if you want the details.

This is definitely an issue... When it comes to archiving, the critical thing really is the lifetime of the storage medium and readers. We seem to be developing storage with higher and higher capacities, but with shorter and shorter life spans. The papyrus medium developed by the Egyptians are still readable today (although the information density is low, and the number of readers are few and far between!), compared to DVD-RWs that can hold a few GBs of data, but only has a shelf life of a few years. Paul Conway has an excellent piece on Preservation in the digital world and takes a look not only at the mediums, but also at the surrounding issues (readers, data formats, etc.).

When it comes to archiving, the critical thing really is the lifetime of the storage medium. We seem to be developing storage with higher and higher capacities, but with shorter and shorter life spans. The papyrus medium developed by the Egyptians are still readable today (although the information density is low, and the number of readers are few and far between!), compared to DVD-RWs that can hold a few GBs of data, but only has a shelf life of a few years.

Paul Conway has an excellent piece on Preservation in the digital world and takes a look not only at the mediums, but also at the surrounding issues (readers, data formats, etc.).

Except that the Bush administration replaced the head of NARA with a more obedient, political appointee. Presumably that is to ensure that key records find ways not to be around when requested.

Sure, we have all the tapes. Yep, stored exactly as specified, retensioned, the whole nine yards. Yep, 68 degrees, 38% humidity. Oh? No, you mean 68 degrees Fahrenheit? Oops, sorry about that.

That's just with the physical medium. Giving records the wrong or mispelled descriptor (aka tag or keyword) will hide them in a database or catalog nicely. Or it will prevent them from being earmarked for longer storage, etc.

http://www.clir.org/pubs/reports/pub121/sec5.html http://www.gpo.gov/su_docs/fdlp/pubs/proceedings/97pro38.html

Standard mass produced CDs will last a maximum of 33 years. I recall reading of outgassing at the foil-polycarbonate interface.

More detailed thoughts on the subject:

http://www.clir.org/PUBS/reports/pub121/sec4.html

http://hardware.slashdot.org/article.pl?sid=05/02/ 05/0024258&tid=198

http://www.itl.nist.gov/div895/gipwg/StabilityStud y.pdf [PDF]

http://www.jts2004.org/english/proceedings/Carou.h tm

http://www.mscience.com/longev.html

And the Google search that lead to these links:

http://www.google.com/search?q=CD+degradation

You should know that the metal alloy film that contains the phase change layer is less stable than the dye used in the -R/+R discs.

NIST did a study of CD and DVD backup methodologies and that statement is part of one of their final reports.

Here's the NIST starting point.

Here's the part about RW vs R longevity.

See this text to get up to speed on some of the best ways to ruin some discs.

For the record, here's what the Council on Library and Information Resources says (emphasis mine):

Flexing (bending) the disc by any means, such as removing it from a jewel case or sitting on it, may harm the disc by causing stresses. The disc should be stored in its case and placed vertically, like a book, on a shelf. Long-term horizontal storage, particularly in a heated environment, can cause the disc to become permanently bowed. While the data may still be intact, the disc may not operate properly in the drive or permit the laser to follow the track. The maximum degree of flex (bend) or number of times a disc can be flexed before it incurs damage is not known. To minimize the risk of damage, it is better to avoid flexing discs.

There is a company that has come out with long-life silkscreened "Our Wedding" DVD-Rs just to make sure that your $3000 wedding video doesn't evaporate on your 5th anniversary.

At 20 C (68 F) and 50% RH, an estimated LE value of ~30 years is indicated. If the storage temperature is raised to 25 C (76 F) at 50% RH, the LE is reduced to ~10 years.

A couple interesting stories from our past and our present along these lines:

The 1960 and 1970 US Census tract level data (tract level means a subdivision of a county) are available only in a proprietary compressed format. This is because the US Government hired a programming firm (Dualabs) to write a compression scheme to be used on this census data. Dualabs wrote the program, compressed the data, and distributed the decompressor program. Census data archivists around the country only got the compressed version of the data. The US Government never made it a point to get the complete corresponding source code to that decompressor program, nor did they get a license to share and modify the program (which would have required source code to do well). The computers people initally used with the decompressor program became outmoded and the decompressor program only ran on that obsolete platform.

Dualabs went out of business in 1974. Therefore, we, the public, paid for Census data we cannot completely read even to this day without reverse engineering the compressed data format. Census data is unarguably important and few people know about this lack of foresight on the part of the US Government and Dualabs. This story has many lessons, most of which still have not been learned.

Recently the University of Illinois at Urbana-Champaign switched from using 5 web-based programs to do class-related stuff online (display student's grades, allow students to receive class material, discuss class projects with each other, etc.). Not long ago, UIUC dropped support for all of these programs and began supporting only Illinois Compass ("powered by WebCT Vista", as the program's proprietors tell us). Illinois Compass is non-free software and costs UIUC one million dollars a year (which UIUC is paying).

UIUC is widely known for having talented software programmers and a highly regarded college of engineering. For orders of magnitude less than $1M/yr UIUC could have paid a few students to leverage the huge pool of capable, tested, and time-honored Free Software out there in order to make a web-based bulletin board system to replace the 5 programs UIUC dropped support for. Now, with Illinois Compass, UIUC pays a team of local support staff (on top of the $1M/yr program fee) to support the new program. UIUC has no source code for Illinois Compass (let alone a license allowing them to share and modify the program). So now UIUC risks running into the same problem the US Government ran into should the proprietor's support for Illinois Compass disappear.

Sometimes these lessons take a long time to learn and cost the public a lot of money.

A quite unhistorical, but probably apt, story comes to us through the Norwegian humorist, Nils Kjaer. At the time of Caliph Omar's invasion of Egypt, the Arab officer on duty in the destruction of the library of Alexandria used two stamps with which he marked the books. One said: "Does not agree with the Koran--heretic, must be burned. The other said: Agrees with the Koran--superfluous, must be burned,"

Japan has compulsory licensing for nonprofit activities involving out of print material. This needs to be looked into for Japanese games. You may have to pay a statutory royalty to the Agency of Cultural Affairs of the Ministry of Education.

Right now we have little dificulty looking at journals (scientific or otherwise) from 150 years ago or more. The pages may be brittle, but the information is there. Obviously, documents thousands of years old still exist and provide priceless information to researches.

The larger goal of electronic preservation is to ensure (if possible) that the electronic data of today will have a lifespan equal, or better, to a physical copy. Right now, this is not possible, and it actually seems that the situation for digital information is worse than for physical data. Think about it, depending on whom you talk to, a CD will last 25-75 years, magnetic media have obvious limitations. Then there is the problem of technology/platform change. How can we guarantee that in 150+ years, PDF, HTML, or even digital data itself will be able to be read? We could be using quantuum computers with some bizarre storage medium taht are completely incompatable with today's technology.

A common solution seems to be to just transfer file formats to tomorrows technology as it is created, and transfer these files from the old media to new as it expires. But at the rate humanity is accumulating knowledge, we could quickly be spending more of our time changing PDFs to whatever, and then that whatever to the next whatever, and so on. Another solution is to maintain the archaic platforms of today so that our files can be read. But, however well cared-for, mechanical devices will break down in time, so that is not a realistic option.

Another possible option is to maintain write emulators for all of the platforms in exsistence today, so that they can run linux or windows or whatever on the badass machines of tomorrow. But that runs into loads of proprietary technology/patent/copyright/legal issues that slashdotters are all well familiar with. Data needs to be freely available to researchers of the future. It should be just as easy (ie, no license required) as it is to pick up a book off the shelf.

So from what I know of digital library collection preservation, the situation at present is pretty grim. We are spending huge amounts of money to rush to publish documents in a digital format, with no assurances that 100 years from now (much less a thousand), this data will be available for general concumption. We are all hoping that it will just "work out" or a technological panacea will emerge.

For more on this topic, try this link.