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Burned CDs Last 5 years Max -- Use Tape?
Lam1969 writes "Computerworld has interviewed Kurt Gerecke, an IBM storage expert and physicist who claims burned CDs only have a two to five-year lifespan, depending on the quality of the CD. From the article: "The problem is material degradation. Optical discs commonly used for burning, such as CD-R and CD-RW, have a recording surface consisting of a layer of dye that can be modified by heat to store data. The degradation process can result in the data 'shifting' on the surface and thus becoming unreadable to the laser beam." Gerecke recommends magnetic tapes to store pictures, videos and songs."
The best way to preserve data, imho is storage independent. Suppose you want to archive your family photos. Sure you can put them on a hard drive... then you can use raid, hard drive will be replaced regulary and the probability of a simultaneous failure being low you dramatically increase the lifespan of your storage. The same could be done on the internet with a P2P network dedicated to long term storage. You divide your files into chuncks and calculate a hash. Peers download it and keep it on their machines. You just have to keep signatures of your chuncks, you can do that on highly reliable mediums, like grave it into stone if you wish. The P2P network automatically polls for chunks and ensure redundancy by pushing rare pieces to clients. To ensure collaboration, you can upload only a fraction of what you host. Some sort of bittorrent expect it's rather a bitpool.
\u262D = \u5350
I've mulled this occasionally, but I suspect the late 20th century and early 21st century will become a mini-dark ages (at least for personal or family things).
The reasons for this:
1. depressingly high failure rate of hard disks
2. lack of long term storage media
3. obsolete formats
As for tape, DLTtape (invented for the venerable VAX) is supposed to be able to last 25 years in good condition. How many people buy DLTtape drives? They aren't cheap and the tapes are not cheap. They are about the only thing with the capacity to store all your photos and video on one cartridge.
Digital photos and video seem like great things (and are: I'd hate to have to edit my videos the old fashioned way) but there is a sting in the tail that most people won't expect. If I want to look at a photograph my Dad took in 1972, I just pull it out the draw and look at it. No maintenance has had to be done on that photograph - it's just been stored in a cool, dry, dark place.
Digital data on the other hand needs periodic maintenance. If a format you've used becomes obsolete, you have to go through and update your entire library. You have to periodically back it up. You have to periodically cut it to media like CD. How much family history have people lost already due to dead hard disks, and not realising the need to continuously back up and format shift? Even if a DLTtape cartridge is still intact and readable in 75 years time, will there be anything to read it? Will JPEG decoders come with everyone's device to view photos?
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The tape companies, obviously.
Seems that with all the recent cost cutting CD-R manufacturers have been using cheaper materials lately. I have CD-Rs that are like 10 years old and still running strong. However, I have some CD-Rs that I have purchased within the last few months and they are already going bad.
http://www.tradealyst.com/
I just recently tested ~120 cds from about 1999-2002.
Attempting to read them with a DVD drive failed many discs.
But reading with a CD drive I was able to read all of them (after some cleaning) except two (most files were readable) that were scratched.
It seem there is some difference between DVD and CD drives.
Most CDs were burned with 2-8x speed, I almost never use >16x today.
For most personal users one DVD will fit everything they need. If they have a big photo collection maybe re-burn all DVDs yearly.
I used to backup to CDROM. Now I back up to DVD. I'm sure something else will come out in the future.
Isn't the cost point close enough yet to just use hard drives instead for long term storage and not be too bad?
You can pick up OEM 250GB hard drives for around $100. Toss in a $50 USB case or a SATA case and you're looking at $1.67 a GB storage. Plus you're not limited to 4.5GB file size.
Sure drives fail but you won't be spinning them that often. I'm begining to think it may be worth it for the long term. Then use the USB drive or SATA as needed and if need be burn a disk.
you were given inferior product. As a side biz I do the same thing and the DVD's I give my clients cost me $12.95 each AND I also give them a DV tape of the raw footage. the DVD blanks and CD blanks I use are archival quality and are very high end. Anyone doing wedding video and photography not using them is simply ripping off their customers.
If they can guarantee 100-year lifespan with a bit of gold then surely the problem with normal discs is over-stated. And that guarantee - does it cover the disc, or the data? No good in 30 years if I want to look at my "family album" - I don't want a blank disc to replace the degraded CD, I want the data.
Great. I lose hundreds of precious photos. They give me a buck.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Also do not touch the coated side of the disc. Cleaning the read-side isn't generally going to degrade it in any way, even if it's scratched those can be buffed out of the clear plastic. The problem is the other side of the disc. The colored/laminated side is the material that gets written to. It's not protected with a thick plastic coating like a real pressed CD. Touching, mashing, or exposing that laminated side to pretty much anything out of the ordinary will shorten the life of the disc.
The ratio of people to cake is too big
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.
"Hey, the third matrix movie would have been good except for the plot,story, and acting." --AC
According to the article the problem with CDR lifespan is that the dyes degrade, not that the metal oxidizes. So it's not clear what benefit you get with using gold.
If they had been recorded on CD-R in 1978, they'd probably be gone now.
Nope. If CD-R technology would have existed in 1978, then the burner would've been a HUGE desk-sized piece of equipment that used a powerful laser to actually burn tiny holes into a thin aluminum disk embedded into a piece of glass. That kind of burned optical digital storage disk would likely last for several decades unless the glass gets broken.
Maximum life is irrelevent. I could draw a picture in the sand with a stick and protect it from the wind for several years -- that doesn't make it a good media to store things in.
If your goal is to preserve data, and there is a 10% chance that exposure to moderate heat will render the media useless, it's time to pick another media.
Conformity is the jailer of freedom and enemy of growth. -JFK
Another comment:
This is a quote from the story: "His recommendation: a hard-drive disk with 7,200 revolutions per minute." That's a way to have secure storage?
That's a recommendation? It's quite obvious that the author of the referenced story, John Blau, has no technical knowledge.
Another quote: "Kurt Gerecke, a physicist and storage expert at IBM Deutschland GmbH, takes this view: If you want to avoid having to burn new CDs every few years, use magnetic tapes to store all your pictures, videos and songs for a lifetime."
I suppose that article was written by a public relations person and was published because someone was paid. Magnetic tapes are NOT reliable, in my experience.
The problem is that the whole concept of arhival storage is no longer workable in the "digital age". Non-electronic media doesn't have enough capacity to store the volume of data we generate today, and electronic media are constantly becoming obsolete. The solution is to give up trying to "archive" data. Just keep it live. Most people upgrade their computer(s) every few years, and each time they upgrade their data storage to a newer system and/or higher capacity. Hard disks are big enough today to store most people's entire data collection, and capacity is growing exponentially. So just keep all your data on a live disk (or disks), back it up regularly on another hard disk, and copy both to new media when you upgrade your computer. Your data will never die.