The Dan’s Data blog has a very interesting article about robust long-term storage and suggests a very novel solution: Use paper for your digital storage…
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But not paper with boring old plain text on it. Paper with arbitrary digital data on it.
Paper is a great format on which to store really important information. Thieves seldom bother to steal it. Magnetic fields or power surges don’t damage it. Paper can also tolerate much higher temperatures than any digital storage system. And if those high temperatures are created by a housefire, paper in a simple wooden box, like the bottom shelf of a chest of drawers, is actually very likely to survive.
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He goes on to describe in detail what kind of digital encoding to use, how to include robust error correction in case of damage, as well as explains how the technological choices he makes are immune against future unavailability (for example, if you’d stored valuable data on an 8-track tape in the ‘70’s, you’d have a hard time finding something with which to read it back today.)