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The spec on LTO is only 15-30 years.

DVD claims 30 to 100 years.

Neither lasts as long as necessary for archival storage.

Actually, it does suggest class and type names. Start here Now, show me more than 15 lines and I'll start to believe it was copied. Say, show me what called RealLogicalDescriptor (and all of RealLogicalDescriptor too) in combination with all of UdfReader.cs. Preferably in text and not in an image. Actually, just give me the MS code and I'll line it up to the ImageMaster code myself.

Top quality DVD+/-Rs will last upto 100 years, theoretically. Top quality CD-Rs upto 200. Even lesser quality DVD+/-Rs and good DVD-R/Ws should last 30 years. No problem using them in this case.

http://www.osta.org/technology/dvdqa/dvdqa11.htm

The only real competitive advantage discs (optical or magnetic) have is cost.

Slow, low density optical discs are good for offline storage, up to 4.7GB at about $0.042:GB. Plus about $1000 for a 400-disc changer jukebox makes about $0.60:GB across all jukebox loads, theoretically also automatable across many loads, for "nearline" storage.

Fast, high denisty magnetic discs are good for online storage, the kind we use as "permanent" without worrying about dealing with them directly (until they fail). They cost about $0.23:GB.

Flash currently costs about $14.00:GB. Obviously archive or real longterm storage isn't threatened right now, except in mobile devices (not just portables with biggish/hottish HDs).

But really mobile devices will have just storage of secrets (keys), pointers (URLs), wireless network interfaces (or HW jacks for the paranoid), and auth UIs (like thumbprint or other biometrics, and maybe still passwords). Because generic computing/comm devices will be everywhere, immersed in wireless networks. Discs have to rotate inside something, but why carry that everywhere, especially when it's fragile? And large capacity is unnecessary in personal tokens, with other tech distributed around the Net.

So while solid state storage is becoming cheaper, the infrastructure that makes it really cheap and easy is growing even faster. By the time a personal token costs $1:GB, it will include wireless/auth interfaces to a ubiquitous wireless Net. And maybe all those spinning discs will go the way of tape: specialized apps that require extreme density, and specialists to operate them.

My concern is that it's lacking a hard disk

Wii has a 512 million byte internal flash drive and a slot for SD cards.

a device which let the X-Box handle games like Halo, a title which would have required long load times on the PS2.

DVD read speeds have increased since the PS2 came out.

I'm going to wait and see how well the Wii handles loading games before I invest in one.

Nintendo's GameCube games didn't need to spend too much time loading. Neither should games on an overclocked GameCube with a remote.

What you're looking for is Universal Disk Format or UDF.

It is an open standard supported by all of the major OSes and manufacturers and is the filesystem of choise for Ultra Density Optical WORM and rewritable disks.

There a drivers for Linux, Windows and all of the major UNIXes. Here is the obligatory Wikipedia entry.

Hard disk filesystems like XFS, JFS, Reiser, ZFS etc. are all wonderful at what they do but they are unsuitable for WORM disks.

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

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

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

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

Or Libraries of Congress per second. DVDs per second isn't a useful rate, unless you're transferring lots of DVDs in a series - which few people do. The much more interesting bandwidth unit is "simultaneous DVDs", multiples of 1.32MBps, 1x DVD speed (9x CD speed). 130GBps is something like 101KDVD:s, which means an audience could watch 101 thousand different DVDs on demand simultaneously over that pipe. That's probably enough for most American cities to have fully interactive TV.

It was my understand (sic) that these areas were accessible by some DVD+RW drives.

Do you have any documentation of this? Any links or accounts of anyone ever actually having successfully done this? Can you provide a first-hand account?

The Optical Storage Technology Association has a great writeup on this (summary: the lead-in area isn't even writeable on consumer DVD media). I'd love to hear what information or any products you have that contradict what they've written.

Idiot.

A quick search on google revealed the UDF Specs:
http://www.osta.org/specs/

For those of you that don't know, UDF is the format that is used by DVDs, but can be used for almost anything.

1. The UDF spec are there - check here.
2. The MultiPlay specification is nothing more than a Logo certification program, and is concerned with physical CD/CD-R/CD-RW compatibility at the Media level for consumer devices (so if you buy a CD player with a MultiPlay logo you know it plays your home-made CD-RW Audio disk).
3. Apparently the CDA format was not released yet (it's a draft). I assume it would be released just like the UDF spec.

Reading the specification is like leafing through a consumer's rights document. All it says is that OSTA will test each player with 5 discs, containing 5 tracks. They will insert the discs, check that all the tracks play in order, and, er, that's it. They then give it a seal of approval.

I always though OSTA was a hardcore technical standards committee. Where's the specification for supported media formats, and how to play them? Where's the filesystem specs (like UDF)? Why are the CD/CD-R/CDRW specs only handwaved?

Reading the specification is like leafing through a consumer's rights document. All it says is that OSTA will test each player with 5 discs, containing 5 tracks. They will insert the discs, check that all the tracks play in order, and, er, that's it. They then give it a seal of approval.

I always though OSTA was a hardcore technical standards committee. Where's the specification for supported media formats, and how to play them? Where's the filesystem specs (like UDF)? Why are the CD/CD-R/CDRW specs only handwaved?

Most hardware that can access DVDs will not allow you to even read the *encrypted* data unless you unlock it first. I'd imagine that means that you would not be able to copy a DVD without DeCSS.

Err .. no.

If you have a DVD-ROM drive and a DVD movie handy, mount it up and examine the directory structure. DVD movies are stored on the media in UDF (Universal Disk Format) format; you can download the UDF specification from the Optical Storage Technology Association. There is a standard directory structure for all DVD-Video discs. For example, the VIDEO_TS directory contains files that contain pointers to the sectors on the media that contain the actual video streams. There is an AUDIO_TS that does the same for audio. If you're interested in specifics on the filesystem, here's a link with more information.

The point is that none of this structure is an industry secret (it's actually a widely-available standard), and nothing prevents you from reading the video or audio content on the CD. The problem is that you cannot meaningfully use it (read: play it) unless you get around the Content Scrambling System. Again, there is nothing that prevents people from doing a direct content-to-content copy of a DVD-Video disc. CSS is meant to restrict use of the content, not readability.