On Thu, 2009-06-11 at 10:38 -0600, Robin Laing wrote: > There was a challenge put out to recover data that was erased with dd > but no takers. The comment that I read on the web site pointed to a > phone call that dd makes it to costly to recover. The title says it all: http://www.h-online.com/news/Secure-deletion-a-single-overwrite-will-do-it--/112432 A few excerpts: "Craig Wright, a forensics expert, claims to have put this legend finally to rest. He and his colleagues ran a scientific study to take a close look at hard disks of various makes and different ages, overwriting their data under controlled conditions and then examining the magnetic surfaces with a magnetic-force microscope. They presented their paper at ICISS 2008 and it has been published by Springer AG in its Lecture Notes in Computer Science series (Craig Wright, Dave Kleiman, Shyaam Sundhar R. S.: Overwriting Hard Drive Data: The Great Wiping Controversy)." "A single bit whose precise location is known can in fact be correctly reconstructed with 56 per cent probability (in one of the quoted examples). To recover a byte, however, correct head positioning would have to be precisely repeated eight times, and the probability of that is only 0.97 per cent. Recovering anything beyond a single byte is even less likely." -- Jussi Lehtola Fedora Project Contributor jussilehtola@xxxxxxxxxxxxxxxxx -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines