> On Jan 16, 2023, at 9:48 PM, Fred Cisin via cctalk <cctalk@classiccmp.org>
> wrote:
>
>> What about M-DISC DVDs and BluRays? Archival grade, not susceptible
> to magnetism or EMP. I think BluRay discs are made of a harder material than
> DVDs and don’t scratch as easily.
>
> On Tue, 17 Jan 2023, Chris via cctalk wrote:
>> Don't know, don't care. If we're being attacked by nuclear bombs of any
>> stripe, I have far more humongous things to worry about then what's on my
>> hard drives. I suppose if you were wring a book and wanted to back that up
>> to an optical disk, go for it.
>
> I care, and would like to know more.
> Even without nuclear bombs, which I stopped worrying about 60 years ago, I
> have occasionally had to deal with damaged data, from causes much more
> mundane than EMPs.
>
> I have had magnetic, AND optical media that have "gone bad".
>
> I am interested in whatever media are more likely to still be readable in a
> few decades.
Not SSD, that's for sure. The fact those are becoming the predominant storage
medium is a bit of a concern for long term storage, because SSD is entirely
unfit for that job. Apparently they are ok when powered because the firmware
will refresh the bits from time to time, but you can't put an SSD on the shelf
and still expect its data to be good a decade later, as you can with hard
drives.
With hard drives you have to worry about mechanical faults, of course. I
wonder if there are any long term storage issues with the bearings.
Most likely, the biggest issue with old storage devices is the loss of the
device to connect them to, and/or the loss of the code that reads them. To
pick one example, I have an 1990s era Dell laptop that no longer passes POST
(it gives a "beep code" failure that I haven't been able to cure). I would
like to get whatever is on its hard disk, but that has a proprietary interface
as far as I can tell and I have nothing to plug it into.
I have an RM03 pack somewhere. There probably are a few places left that could
read it. If it were an RA60 pack it would be a whole lot more problematic, I
suspect. Without an old drive, how would you recover the data? Spin table?
Perhaps, if you can find, or reverse engineer, the format.
The Long Now foundation has done work on the question of storing data in a way
that can still be deciphered a millennium from now. It's not a simple
question. Some SF writers have wrapped stories around the question (James P.
Hogan did it several times -- Echoes of an Alien Sky, Inherit the Stars, and
much earlier (1957) there was H. Beam Piper "Omnilingual").
Early storage devices are less problematic than newer ones, given the more and
more complex coding used. Never mind intentional encryption; just the high
density codes with interleaving and ECC and all that would be somewhat akin to
encryption when examined with a future archeologist. Imagine, for example, an
archeologist 5 centures from now trying to make sense out of a box full of SATA
interface hard drives, full of documents in PDF, JPG, or MP4 format.
paul
