The longer you leave a 0 or 1 in a given place on a platter the more of
an "impression" it makes there. Writing over it with with random bits,
even several times, will not totally erase the deep magnetic impression
of the former bit. Forensics are more than good enough to pick that up,
if you pay the money.
As always, the real question becomes how much of a chance is there of
someone getting an old hard disk, and how much damage would be done if
they read the data on it. This is where is usually falls apart. People
want to completely wipe a disk, but want that to be essentially free in
cost and hassle. Tough cookies. If it's worth it, then completely
destroy the drives. If it's not worth it then write random data on it a
few times and call it good. But make an informed choice. Writing random
data might stop joe blow, but it won't stop someone serious with a lot
to gain.
On Mon, Dec 31, 2007 at 05:36:46PM -0600, Marco Peereboom wrote:
