Re: [Full-disclosure] Disk wiping -- An alternate approach?

[T Biehn <tbiehn@xxxxxxxxx>]

Overwritten files require analysis with a 'big expensive machine.'
I doubt they ever recover the full file.

-Travis

On Tue, Jan 26, 2010 at 11:04 AM, Christian Sciberras <uuf6429@xxxxxxxxx> wrote:
> I was thinking, since all this (reasonable) fuss on wiping a disk over 10
> times to ensure non-readability, how come we're yet very limited on space
> usage?
> If, for example, I overwrote a bitmap file with a text one, what stops the
> computer from recovering/storing both (without using additional space)?
> Just a couple curiosities of mine.
>
>
>
>
>
> On Tue, Jan 26, 2010 at 4:08 PM, Michael Holstein
> <michael.holstein@xxxxxxxxxxx> wrote:
>>
>> > By the way, does somebody knows about the flash memory?
>> > Is zeroing a whole usb key enough to make the data unrecoverable?
>> >
>>
>> No, wear-leveling (done at the memory controller level) will dynamically
>> re-map addresses on the actual flash chip to ensure a relatively
>> consistent number of write cycles across the entire drive.
>>
>> The only way to completely "wipe" a flash disk is with a hammer.
>>
>> Regards,
>>
>> Michael Holstein
>> Cleveland State University
>>
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