Hi Dennis, Quoting Dennis Lindahl <[EMAIL PROTECTED]>:
> Once information on a digital media has been overwritten, it cannot be > recreated/restored in any lab. All this talk about electron microscopes > and overwriting in multiple passes is just a load of crap derived from > an old DoD standard. It has no practical meaning. One overwrite is > enough. Please let this ugly rumour die :) You seem a little quick to discount something as impossible. Do you think Military choose physical destruction for the heck of it? IBAS can't do it on the cheap, so they claim it impossible? And you take that as gospel? The nature of digital signals comes down to thresholds. The actual analog values are not absolutely digital and remnants often remain. When you open up a storage device and circumvent the part which enforces and interprets the thresholds which define what constitutes a one or a zero, you then have the ability to see the remnants without the masking effect of those digital parts. If only zeroes where witten to the disk, these remnants stand out and make it easier to reconstruct the original data. By overwritting with ones, zeroes (or an alternating pattern of ones and zeroes) and then random data, the remnants become lost in a sea of noise. http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html It comes down to cost/benefit. The fact that you don't hear about it much is because it is costly and time consuming. Just because you can't do it at home, does not mean it can't be done. Shane J Pearson ------------------------------------------------------------ This email was sent from Netspace Webmail: http://www.netspace.net.au
