OT: Archiving data (LONG)

From: Don Maslin <donm_at_cts.com>
Date: Wed May 31 13:10:52 2000

On Wed, 31 May 2000, McFadden, Mike wrote:

> Archiving data has as many definitions as there are people interested in it.
> At work we talk about archiving x-ray images on film for 7 years for adults
> and 25 years for children. Physical loss of the data is more of a problem
> than deterioration of the media. I have data on 12" optical packs that are
> 5 years old and there are conversion/data retrieval services that will
> retrieve my data but the cost is prohibitive. If I tell the powers in
> charge (PIC) that it will cost them $5 to retrieve an image that was created
> for $1 they think I am crazy. However if there is a lawyer making the
> request and the risk is $10,000,000 then the PIC are happy to pay.
>
> Currently we may have for a single patient's cardiac angiography study about
> 1,000 35mm images, about 1 GB. The system now uses CDROM-RW and puts the
> images all on 1 CD using JPEG compression, they swear it will last 25 years.
> I guess we will wait and see.
>
> The big issue for magnetic media archival is that it is an ongoing process
> with very few retrievals ever actually requested. If every 5 years I need

>From my experience, the retrievals of 'legacy' disk images is something
above 'very few'. In about the past six years I have provided disks
on about 385 individual orders, usually for multiple disks. Virtually
all of this from TeleDisk images stored on a hard disk.

                                                 - don

> to refresh my magnetic data then I have a reoccurring cost. This seems to
> be what many DP operations are planning. If I ask for lots of dollars for
> saving old data most organizations will laugh. I'll bet when reality or a
> lawsuit hits they will hope to beg forgiveness for loosing the data.
>
> Most media storage lifetimes are extrapolated from accelerated testing and
> assume optimal humidity and temperature. If you want proven lifetimes then
> there are only several known/proven methods. I know the government and the
> Mormons, two separate entities, are storing data etched on iridium
> substrates in human readable form. They talk about lifetimes of 1,000's of
> years. Other examples are stone tablets, photographic film, and paper. I
> think that we can eliminate stone tablets for storing magnetic data. Paper
> seems to be cumbersome and is fairly fragile. That leaves photographic
> methods. Photographic images from the Civil War still exist. Source code or
> HEX dumps on photographic media may be the best way.
>
> Maybe photographic film quality "paper tape" is the answer. The other
> solution may be photographic film floppy disks. I'd better get right off to
> my patent attorney and file.
>
> I've started babbling.
> Mike
>
>
>
Received on Wed May 31 2000 - 13:10:52 BST

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