From: "Arthur T." <arthur@munged.invalid>

| On another list, someone asked a question which piqued my
| curiosity.
|
| U.S. DoD requires 7 overwrites. The OP wanted a '*technical*
| justification of "15-times" or any other number. Technical one,
| not "because mama said so".'
|
| Has anyone actually recovered data that's been overwritten
| even once by random data? Twice?
|
| We know about the theoretical techniques to get the data. We
| know it would be horrendously expensive. But has anyone
| *actually* done it?
|
| And, regardless, is there some number of overwrites that
| *will* make the data unrecoverable? The OP was looking for
| something better than pulling a number out of the air (or
| wherever) - a number with some theoretical or experimental
| justification.
|
| I figured if anyone had the answers (and was allowed to give
| them), it would likely be someone in this group.
|

The DoD requirements are...

Write a bit pattern such as; 10101010
Write its complement; 01010101
Write another pattern such as; 11110000

Perform that six times.

The disk will then be sanitized.

--
Dave
http://www.claymania.com/removal-trojan-adware.html
Multi-AV - http://www.pctipp.ch/downloads/dl/35905.asp