Disasters and Recovery

From: Doug <doug_at_blinkenlights.com>
Date: Sun Jan 17 22:04:22 1999

On Sun, 17 Jan 1999, Sam Ismail wrote:

> What are you talking about? The whole aversion to using CD's was the fact
> that they have a theoretical shelf life of only 50-100 years. Like I
> said, the Dead Sea scrolls lasted more than two millenia without much
> thought going into how to preserve them. And here you are talking about
> going thru the trouble of filling a chamber with inert gasses to promote
> preservation. Unless your line of thinking is to fill the chamber with
> water just to give paper a challenge.

I really think you're mixing two concepts here. Do you think a "shelf
life of 50 years" means that the thing disintegrates completely in 50
years, or do you think it means that under "normal" conditions you can
expect some data loss in 50 years?

> 100 copies on what? 100 other EPROMs? On CD? Or encoded on paper?

In the same device! Don't pack the data so densly that a one-bit error
makes the whole thing worthless. Expect that one bit in N will have an
error over time, and increase the redundant info by at least a factor of
N.

-- Doug
Received on Sun Jan 17 1999 - 22:04:22 GMT