While I agree with Bill's thinking about the retrieval of data in the future, one shouldn't overlook the critical part of the whole affair: MAKE A QUALITY BACKUP. The issue of being able to recover the data in the future will be a moot point if the files are corrupt from the beginning. To this end, one should choose the highest quality media available. There are GREAT differences. A bit of research is in order. For those interested, here is a good place to begin:
http://dpbestflow.org/node/260 ===Carl Kunath ----- Original Message ----- From: Mixon Bill To: Cavers Texas Sent: Sunday, November 15, 2009 2:00 PM Subject: [Texascavers] archiving your cave data Don't spend extra money on "archival" CD-Rs or DVD-Rs. As I've pointed out before, _any_ such media, properly stored (which doesn't mean in sealed in dry nitrogen, just in a case, upright, like a book on a shelf, in normal indoor environment) will "outlast the technology," which means that the data on it will be good when you no longer have anything that will read it. Estimates for R media are at least 200 years; for RW, 50 years. Those little hard-shell 3.5-inch floppies were introduced only 25 years ago; seen one lately? I don't think even David's elaborate scheme of including the necessary hardware in a time capsule would work. Modern computer chips will probably not last that long even if not powered, due to diffusion of the atoms in the extremely tiny features. Anyway, there wouldn't be any convenient way to get the data out of the computer, even if you could read it on screen. Who will have a USB cable 500 years from now? Just assume electonically archived data will have to be recopied every twenty years to keep up with hardward and software evolution. Or of course, for the Luddite, good-quality paper or black-and-white microfilm film are considered archival and don't require much equipment to read. -- Mixon
