<MACENTERPRISE@LISTSERV.CUNY.EDU> FYI: Rendering Drives Completely Unreadable Can be Difficult ------------------------------------------------------- The National Association for Information Destruction has said it cannot endorse the use of wiping applications alone for ensuring that data have been effectively removed from hard drives. NAID executive director Bob Johnson said the only way to ensure that the data will be unreadable is to physically destroy the drives, and even that has to be done in certain ways to ensure its efficacy. Most major PC makers offer a drive destruction service for $20 or $30. Some hardware engineers say they understand why the drives have been created in a way that makes it hard to completely erase the data: customers demanded it because they were afraid of losing information they had stored on their drives. http://news.com.com/2102-1029_3-5676995.html?tag=st.util.print [Editor's Note (Pescatore): Cool, I want a "National Association for Information Destruction" tee shirt. How hard could it be to have an interlock feature - you can really, really clear the drive if you open the case, hold this button down while you delete? (Ranum): Peter Guttman, from New Zealand, did a terrific talk in 1997 at USENIX in which he showed electromicrographs of hard disk surfaces that had been "wiped" - you could still clearly see the 1s and 0s where the heads failed to line up perfectly on the track during the write/erase sequence. He also pointed out that you can tell more recently written data from less recently written data by the field strength in the area, which would actually make it much easier to tell what had been "wiped" versus what was persistent long-term store. The paper, minus the cool photos may be found at: http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html Hard disks, I've found, make satisfying small arms targets.] Here is Mac OS X software called "SPX" that uses the "Guttman" method of securely deleting data off a hard disk. If you want to donate old HD's this might be the best method for protecting your data that was on the HD other than physically destroying the HD's. http://rixstep.com/4/0/spx/ -- Thanks: Richard Glaser University of Utah - Student Computing Labs richard@scl.utah.edu 801-585-8016 _____________________________________________________ Subscription Options and Archives http://listserv.cuny.edu/archives/macenterprise.html ----- End forwarded message ----- -- Eugen* Leitl <a href="http://leitl.org">leitl</a> ______________________________________________________________ ICBM: 48.07078, 11.61144 http://www.leitl.org 8B29F6BE: 099D 78BA 2FD3 B014 B08A 7779 75B0 2443 8B29 F6BE http://moleculardevices.org http://nanomachines.net [demime 1.01d removed an attachment of type application/pgp-signature which had a name of signature.asc]