In German Archivists Go Retro for Data Preservation, Deutsche Welle (German public broadcasting) reports on the Fraunhofer Institute figuring out how to store digital data for hundreds of years. (Fraunhofer is best known as the inventor of MP3.)
The life of CD and DVD discs is assumed to measure in the years, maybe decades at most. That seems impotent compared to parchment (animal skin), which lasts 1000 years. Instead, the Instutite returned to a technology of the 1960s: microfiche.
The Instutute uses three colors to store 6MB of data per 40x45 sq mm micofiche card -- 2MB per color. While 6MB represents just 6 minutes of music in MP3 format, it is highly efficient for plain text: one million words. The The automated ArchivLaser machine writes 1TB of data a day.
With digital data saved on analog film "you have directly readable information that is independent from an operating system and from any kind of machine that might not be available in five years," said Wolfgang Riedel, project manager at the institute. "Who can still read a floppy disk?" Accessing data on microfilm doesn't require here-today-gone-tomorrow technology: In a pinch, microfilm can be read with a loupe or microscope.
I wonder how we'd go about archiving CAD drawings on microfiche?