Printing Keys and using OCR.

[David Shaw]

On Fri, May 18, 2007 at 07:41:06PM +0100, Benjamin Donnachie wrote:
> David Shaw wrote:
> > For paper to last 100 years is not even vaguely impressive.  Paper
> > regularly lasts many hundreds of years even under less than optimal
> > conditions.
> 
> All seems rather academic to me as I would expect the current encryption
> algorithms to be rendered useless by then.

Your point does not follow.  There are many "useless" algorithms that
are still vastly stronger than the attack that most people can bring
to bear.  Let's say that I printed a DES (1970s era single DES) key on
paper.  DES is "useless" today, but unless I wanted to invest
significant money and time in key cracking (even though it would
eventually succeed), I should really keep that paper around and not
rely on DES being useless.

Even so, you snipped part of my comment in your reply.  The point is
not only that paper lasts effectively "forever", but also that optical
disc doesn't last long enough.  For many key-on-paper uses, it doesn't
matter much if paper lasts 100 years or 1000 years.  It only matters
that it lasts longer than I need it to last (e.g. will it last longer
than I will).  Optical disc doesn't last that long.

David