Robert Newson writes: > P Witte wrote: > > ... >>> I have serious doubts whether modern, CD-ROM based systems could keep >>> the data for so long. I would never use CDs or DVDs for long-term >>> storage of important data. >> CDs and DVDs are the "medium of the day" (as were microdrives and >> floppies in their day). Round the next corner are HD and Blu-ray, >> perhaps, so then we'll have to copy all our important data once again. > > Wasn't there a report [fairly] recently about writeable CDs becoming > unreadable after a while, the time also dependent upon method of labelling > said CD? > > see, eg: > > http://searchwincomputing.techtarget.com/tip/0,289483,sid68_gci1157306,00.html > http://www.postgazette.com/pg/04127/311683.stm > http://photo.net/bboard/q-and-a-fetch-msg?msg_id=00EoLc
No one knows how long CD/DVDs will really last. Guestimates range from two to 100 years, depending on the quality of media, the recorder, how they are recorded, how handled, labelled and stored (and who you want to believe). And this is exactly my point: To be sure, important data should always be backed up to "the medium of the day". But this is not enough, as there are more serious threats to precious data: Obsolescence; ie not being able to read the disk due to no longer having a compatible device to read the medium, or being able to find or to run the software required to interpret the data. I had a Psion S3 pocket computer for some years. And although I conscientiously backed up the data to my QL (via QTPI and some home-grown programs) much of it can no longer be read as the device (the Psion S3) no longer works and therefore also not the applications used to create and read the data. Serendipitously, with uncharacteristic (and commendable ;-) prescience I also made backups in "export" format (ie either in plaintext or comma delimited plaintext data) so that, apart from any formatting, the data itself is mostly still intact. (The thought of Unicode becoming standard still freaks me, though!) The programs I wrote for this machine are, of course obsolete and useless. Changes to file formats is another worrying problem. M$ Orifice changes its file formats approximately every other major release. Provided you stay with the M$ bandwagon and keep upgrading regularly, it shouldnt be too difficult to keep reading your old files. But it is not unlikely that you may find that files produced with less mainstream programs may no longer be readable by a later version of the same program 10 years hence. M$ is releasing a new picture format that they hope will replace the now so familiar jpeg format. No doubt we will all jump on that bandwagon eventually, as the technological advantages will prove too alluring in the long run (and you will be struggling against the grain to use any other format anyway). For a while we will keep our eye on the ball and not worry about our old photos and stuff. But then we will either have to convert all the old stuff to the new format (perhaps loosing the original file date information etc on the way) or find that we have to purchase or write converters for them (if we can still find an old fashioned Ultra Blu-ray drive to read the disks).. M$ dont care about your personal data, otherwise they would have thought about it when they designed their OS. But they didnt, did they? Why else would they hide your vital correspondence behind two sets of hidden folders deep down in the system partition of your disk? (Outlook's proprietary data file containing emails, agendas etc, resides at %system%:\Documents and Settings\username\Local Settings\Application Data\Microsoft\Outlook\outlook.pst) Oh well, just backup your entire disk then, they will say. The problem is that by doing that you also back up a whole heap of totally unnecessary stuff, thereby creating extra work for you and a logistical nightmare, as each unnecessary KB of data you back up eats up your time, money and patience, and increases the chances of error, loosing stuff, missing stuff or just not bothering. In other words, if you take your data seriously you cannot leave it to anyone else to keep it safe and accessible. Per _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
