If you want to get into physical longevity, there should be some reports from the US National Archives.
Their missions is "Data for the lifetime of the Republic", and they often think in terms of centuries for storage. I know that they had asked NIST to do some studies in the past. I know that in the past they had done some accelerated aging test on various media. Not surprisingly, really old 9-track (6250 bpi PW) had a lifetime nearing a century, if the tape was re-tensioned every few years :-) CD and DVD have shelf lifetimes 5-10 years, as neither of those was really designed as an archival media. But material and manufacturing variability are all over the map per disk, so there's no consistent lifetime. http://www.thexlab.com/faqs/opticalmedialongevity.html http://www.archives.gov/records-mgmt/initiatives/temp-opmedia-faq.html Blu-ray and Sony's new (joint with Panasonic) Archive Disk is designed to have a lifetime of about 50 years. AD is a follow on to Blu-Ray technology. https://pro.sony.com/bbsc/ssr/cat-datastorage/cat-opticaldiscarchive/ On Fri, Dec 5, 2014 at 11:28 AM, Edward Ned Harvey (lopser) <lop...@nedharvey.com> wrote: >> From: berg...@merctech.com [mailto:berg...@merctech.com] >> >> My biggest concern about the longevity of disk drives for off-line storage >> would be mechanical. A disk drive has a fair number of moving parts, >> which have been designed to move, not sit still for extremely long >> periods. Many years ago, disk drives were well known for having problems >> spinning up if they were shut down for too long -- typically the problem >> was ascribed to stuck bearings, congealed grease, etc > > One of my cousins is a very well educated librarian. She told me, decades > ago they converted all the old centuries-old fragile paper books to > microfiche, which has all now deteriorated, and the centuries-old paper books > remain unchanged. She was asking me about data longevity on digital media, > which they're currently in process scanning onto. My answer reaffirmed her > suspicion that the new digital media is probably less reliable than the > original paper, but at least the digital media has the option of being > actively upkept, and will survive as long as you do regular upkeep diligence > and maintain redundancy. > > So print the entire contents of every backup on paper and store the paper > offsite in a waterproof, fireproof box. ;-) > _______________________________________________ > Tech mailing list > Tech@lists.lopsa.org > https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech > This list provided by the League of Professional System Administrators > http://lopsa.org/ _______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
