shredding files on a flash drive

[James Knott]

Kristian Erik Hermansen wrote:
> On Jan 25, 2008 11:00 AM, James Knott <james.knott-bJEeYj9oJeDQT0dZR+AlfA at public.gmane.org> wrote:
>> Can you be so certain?  Many years ago, I used to maintain mini-computer
>> systems, including disk drives.  There were many times I would repair a
>> drive after a head crash and then do an alignment of the heads etc.
>> When you do that, one thing that's obvious is that the data is recorded
>> in clearly identifiable tracks, which you can locate by watching the
>> recovered signal with an oscilloscope.  What's to stop someone from
>> reassembling those platters in a similar drive and, with perhaps some
>> effort, recovering that data?  It may be difficult, but I not
>> impossible.  I know it's possible to align a drive to the data on a
>> disk, because I've done it.  You might also want to talk to someone in
>> the data recovery business.  IIRC, there was a presentation by one such
>> person at a TLUG meeting a few years back.
> 
> I have spoken to people in the data forensics field, yes.  With
> multi-platter disk drives, I encourage anyone to prove me (and the
> forensics guys) wrong.  The problem is that newer disks are aligned
> and sealed at the same time in the factory.  The tracking information
> is written to the disk while it is enclosed.  I don't see how you
> would determine how to align the tracks from data which you cannot
> determine is valid data or not.  Please explain and show proof.  Btw,
> I have done and consulted with forensics experts about the situation
> you speak of -- using a similar drive to recover data.  I encourage
> anyone to provide evidence that it is possible.  There is no evidence,
> that I have seen, to support it.  However, there is a multitude of
> evidence to show that once you misalign the platters, your data is
> toast...

Further on this.  Here's a link from a data recovery service.
http://www.salvagedata.ca/hard-drive-recovery/

And a quote from that page:

"We provide recovery service for all types of hard drives including 
SCSI, ATA, IDE, and SATA internal drives. Our detailed comprehension of 
these storage devices makes for a quick and easy recovery and, when 
needed, a team of senior engineers can develop custom solutions for even 
the most complicated recoveries.

With years of experience behind us, we've rightfully established our 
credibility as the lead experts, specializing in the field of 
professional hard drive data recovery. We support and perform data 
recovery on drives of all makes, models and sizes, from the latest 
quarter-sized mircodrives to the oldest Bigfoot ATA hard drives. 
SalvageData engineers utilize an exclusive knowledgebase, consisting of 
technical expertise and valuable industry experience to produce 
first-rate results. Our advanced HDD recovery tools, combined with the 
credentials gained from working on a wide range of drive failure and 
disaster recovery cases, make us the trusted source for experts seeking 
critical data recovery services.

Through years of industry involvement, SalvageData has established a 
sterling reputation for recovering data from failed computer hard disk 
drives (HDD), with an unparalleled rate of success.

We provide recovery service for all types of hard drives including SCSI, 
ATA, IDE, and SATA internal drives. Our detailed comprehension of these 
storage devices makes for a quick and easy recovery and, when needed, a 
team of senior engineers can develop custom solutions for even the most 
complicated recoveries.

Organizations, businesses, and individual home users can be comfortable 
when turning to SalvageData Canada for their hard drive recovery needs. 
  When the data matters most, you can be sure that your hard drive is in 
good hands with our qualified SalvageData Canada experts.

Our commitment and dedication to R&D allows us to support more hardware 
and system platforms than most competitors. So, regardless of how the 
data loss occurred, we have the expertise to recover data that others 
might simply consider unrecoverable."


They work with more than just deleted files.  They recover data from 
drives with severe hardware damage.  Sometimes, such as after a fire, 
the only recourse is to pull the platters out and mount them in a 
similar drive.  IIRC, this was mentioned by the presenter at the TLUG 
meeting a few years back.



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