Last I heard from some DoD/NIPC people (and this was well over a year ago) is that they were able to successfully retrieve at least partial information off a disk that had been overwritten 153 times. Assume that (at least government) forensic techniques have improved since.
Hope this helps! Regards, Greg van der Gaast Ordina Public SDS West Security Services -----Oorspronkelijk bericht----- Van: Carol Stone [mailto:carol@;carolstone.com] Verzonden: Tuesday, October 29, 2002 9:58 PM Aan: [EMAIL PROTECTED] Onderwerp: Re: Interesting One I don't know much about this, but yesterday I read in one of the later chapters of Bruce Schneier's book, "Secrets and Lies," (link to amazon follows) that over-writing data on a disk does *not* completely obliterate it, it just makes it a lot more difficult to recover with each over-write. I believe he said just how many re-writes were still recoverable was a secret one of our governmental organizations wasn't about to give up. I'll look at my book later when I have it in my hands and see if I can't find part and post a pointer to *his* reference. -carol http://www.amazon.com/exec/obidos/tg/detail/- /0471253111/qid=1035924654/sr=8-3/ref=sr_8_3/104-4454644-5987143? v=glance&n=507846 > Greetings Folks, > > I had an interesting conversation today with someone from FAST > (Federation > Against Software Theft) They pretend not to be a snitch wing of the BSA. > Anyway, to get to the point, the guy that came to see me said that their > forensics guys could read data off a hard drive that had been written > over > up to thirty times. I find this very hard to believe and told him I > thought > he was mistaken but the guy was adamant that it could be done. My > question > is, does anyone have any views on this, or, can anyone point me to a > source > of information where I can get the facts on exactly how much data can be > retrieved off a hard drive and under what conditions etc etc. > > Thanks > > Dave Adams > > > > This message (and any associated files) is intended only for the > use of the individual or entity to which it is addressed and may > contain information that is confidential, subject to copyright or > constitutes a trade secret. If you are not the intended recipient > you are hereby notified that any dissemination, copying or > distribution of this message, or files associated with this message, > is strictly prohibited. If you have received this message in error, > please notify us immediately by replying to the message and deleting > it from your computer. Messages sent to and from > John Crowley (Maidstone) Ltd may be monitored. > > Internet communications cannot be guaranteed to be secure or error- free > as information could be intercepted, corrupted, lost, destroyed, arrive > late or incomplete, or contain viruses. Therefore, we do not accept > responsibility for any errors or omissions that are present in this > message, or any attachment, that have arisen as a result of e-mail > transmission. If verification is required, please request a hard-copy > version. Any views or opinions presented are solely those of the author > and do not necessarily represent those of John Crowley (Maidstone) Ltd. > > -- Real people for the virtual world. http://www.elirion.net