"RPR" wrote in message
oups.com...
Basically you'll have to copy the data to state of the art media about
every decade. Don't try to store spare drives for the future, that
doesn't usually work - electromechanical devices age when they're not
in use too.

In addition to Ralf-Peter's comment, you better think long and hard about
how you will be accessing that data 50 years from now, from an application
point of view. 50 years from now, the computing devices will be radically
different from today's PC's. Unless you have documented every bit about the
format of the files you stored and the environment you need to recreate the
information, even migration to state of the art media will not help.

Consider a Word Perfect 4.2 file from 20 years ago. You'll need some effort
today to open and read such a file. Because the format is relatively simple,
you can still read the text using any hex editor. But recreating the page
formatting maybe harder already.

Now consider your MP3 and picture files which are heavily encoded en
compressed, and fast forward to the year 2055. Unless you know exactly how
they are recreated, all you'll have 50 years from now is a bunch of zeroes
and ones. This is scary for single files, but things are even worse when
multipple files form a single context. Think databases with external
pointers. Think HTML files with web links. How much of that will exist 50
years from now?

For permanent long-term records, store the information on a medium that can
be interpreted by the most universal and long-term computer you have - the
one between your ears -. Microfiche and dead trees aren't obsolete just
yet...

Rob