9 Mar
2011
9 Mar
'11
8:26 p.m.
Eric Smith wrote:
Of course, for classified data and any other data that
needs to be
secure from even extremely well-funded adversaries (i.e., intelligence
agencies), physical destruction is still the only satisfactory erasure
method. But telling the flash drive to do a secure erase should be
good enough to keep even the commercial data recovery companies from
being able to extract your credit card numbers, etc.
If the secure erase feature is not available, then if it can be assumed
that there are no bad blocks with valid date and hidden away, about
how many time does it take to completely erase a hard disk drive block
for both ATA and non-ATA hard drive beyond all possibility of recovery?
In the past I have heard that a variable bit pattern written to a disk
block around seven times is sufficient to prevent the original data
from being recovered.
Jerome Fine