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Ever reported data recovering from broken CD/DVD/HDD?

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Beetle
(@beetle)
Posts: 318
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I suggest the OP carry out a bit of an experiment with a CD.

To the OP…

Take one and snap in half with your hands ( wear gloves! ). You will see that the substrate ( that's the silver material ) will pulverize along the fracture lines into a lot of little pieces. I don't know how you could re-assemble a useable readable CD from these tiny fragments. As for HDD with a hole drilled in it, I doubt a drive head would survive passing over the resulting burrs.

I think if the OP does some observation of the physical properties of a broken ( not scored ) optical disk he will see what Jaclaz is getting at.

 
Posted : 21/01/2013 1:15 am
jaclaz
(@jaclaz)
Posts: 5133
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Why do you get angry, jaclaz? D

Because I feel that at least big parts of the "sent messages" don't go through and never reach you.

surely I don´t expressed correctly or perhaprs you dont understand me. I just asked if I can know,recognize which of the 3 categories you stated fits any specific hard drive, for example the old ones I have.

And you already asked a very similar question and you were already replied, you need to know, capacity, number of platters, derive areal density, cross-check with manufacturer specs when available, compare with year of production, verify with several different sources, then, you will be able to make an educated guess.

And of course there are many more than three categories - hence the concept of "simplified list".

Now try reading carefully and attentively the quoted sentence (of which I have highlighted some relevant parts that you seemingly missed)

The answer is that - at the state of the art - (and EXCLUDED what the National Security Agencies may have in their secret labs) a single, neat or rough, cut through a CD/DVD, passing through the center hole and thus dividing the CD in two pieces is enough, even if you have both pieces, to avoid the reading of any data from it with any commercially available device.
This doesn't mean that it is "impossible", only that noone has ever documented the successful recovery of any data from such a damaged CD/DVD.

So. let's try again AFTER having ALREADY discussed in detail what "secret" means
http//www.forensicfocus.com/Forums/viewtopic/p=6562637/#6562637

Three points

  1. What the G-men can (or cannot) do is SECRET (noone except them and a few other authorized people that will keep their mouth shut know exactly what they can do).
  2. There is NO commercially available device/method to recover data from a broken CD (again to the best of my knowledge).
  3. There is/was an experimental theory and an experimental project aimed to read data from a CD through imaging it with a microscope (and a link was given to the report about that research).
  4. [/listo]
    I hope there is no issue with items #1 and #2 above.

    About #3, if you READ that document, you will possibly gather that (again main points, if you read it attentively you will find more) that the experiment was made on a non-broken CD, on page #16 "Present technique" is estimated at 67 year time to read a complete CD, what was written to the CD was not "random data", but it was a specific sized (very small) grey scaled bitmap (i.e. a non-encoded file that can be easily be represented partially if partial data is missing) forming a "pattern" repeated over and over (and they knew where this info was written to on the disk surface and conversely where to look at and also what to look for).
    The CD used in the experiment is NOT broken into pieces.

    That is a report about an EXPERIMENT that proves an UNDISPUTED theory (a media that is read through optical means may be read also through different optical means), but that besides the good results is NOWHERE representing a viable data recovery method.

    IF - over the more than 8 (eight) years elapsed since - they have managed to reduce the time from actual 67 years to the hypothetical 475 hours (or less) AND IF *something else* is invented to "keep together" the pieces of a broken CD on the spin AND IF precision is bettered as to allow NO reading errors (and thus recover encoded data formats such as .jpg or .zip) AND IF this enhanced precision can be extended on a sensibly bigger data extent (the WHOLE SIZE of the file that was partially recovered was 11 Kb) AND IF this can be reproduced over several makes/models/brands of CD (both "pressed" and "burned") THEN they would have something that might develop into a commercial device (which costs I won't even dare to guess-estimate).

    And in any case it would ALREADY be late, as the CD is not used anymore and DVD has a MUCH HIGHER data density (thus posing new issues).

    jaclaz

 
Posted : 21/01/2013 1:41 am
(@williamsonn)
Posts: 85
Trusted Member
Topic starter
 

jaclaz. thanks for your patience and kindness, but not get angry, please 😉 I appreciate much your interesting information. Now, ALL IS MUCH more clear for me.

Only a question more, please. Your last words are not totally clear for me

"And in any case it would ALREADY be late, as the CD is not used anymore and DVD has a MUCH HIGHER data density (thus posing new issues)."

Do you mean that DVD recovering, more currenly used than CD, and having, of course much more density


Would be more difficult to read f broken, or, instead, easier?


Again, thank you very much )

 
Posted : 21/01/2013 5:27 am
jaclaz
(@jaclaz)
Posts: 5133
Illustrious Member
 

Do you mean that DVD recovering, more currenly used than CD, and having, of course much more density


Would be more difficult to read f broken, or, instead, easier?


Let's temporarily forget about broken optical media.
Let's check your eyesight. 😯
Following are two text lines, which one can you read more easily wink ?

  1. This line represents some text written on a CD.
  2. This line represents the same line but written to a DVD.
  3. [/listo]

    But, when you go beyond the first impression (and get yourself a suitable magnifying glass to read the second line) you might want to consider how this also implies that you have to break DVD's in smaller pieces as a DVD fragment the same size you used to break CD's into may contain as much as 13 times the amount of information than a CD fragment.

    jaclaz

 
Posted : 21/01/2013 3:33 pm
(@sgreene2991)
Posts: 77
Trusted Member
 

According to a friend in Federal LE, under the right circumstances they can recover portions of data from a CD or DVD. What those circumstances are and what tools they use I couldn't find out. HDDs are a little different. If the platter has been dinged, dented, scratched, touched, or anything of that sort, it is highly unlikely that you will ever be able to get anything off of it. So to solve that, I just use HDDs for target practice. Plenty of dirt, lead, and dings to keep everything out of someone elses hands. And they're very resilient, which means you can hit them multiple times!

 
Posted : 22/01/2013 4:31 am
(@williamsonn)
Posts: 85
Trusted Member
Topic starter
 

I now understand better. However, if "… you have to break DVDs in smaller pieces as a DVD fragment the same size you used to break CD's into may contain as much as 13 times the amount of information than a CD fragment." then I do not understand why are not at least a few reports of DVD fragments recovering, being at least 13 times easier to get data from them than from a CD.

 
Posted : 22/01/2013 7:33 am
(@williamsonn)
Posts: 85
Trusted Member
Topic starter
 

Or said more correctly Not 13 times easier(as if there are no report then I suppose the difficulty has to be the same)but containing a DVD much more density of information perhaps I think it shoud be easier to recover data.

 
Posted : 22/01/2013 7:38 am
jaclaz
(@jaclaz)
Posts: 5133
Illustrious Member
 

I guess we are speaking two too different languages.

Information on DVD is "more densely written" than on CD's.

Reading

smaller characters

is more difficult than reading

BIG ONES

.

And we do not have even a single valid report of anyone actually reading data from a broken CD (i.e. written in

easier to read

characters).

When we will have one, then the technique applied may possibly be refined, bettered, made more accurate, so that even

smaller characters

could be read.

@sgreene2991
Well, the Fed's can also (or are sometimes cited as being able to) decrypt *any* encrypted hard disk
http//www.wired.com/threatlevel/2012/02/decryption-flap-mooted/
or maybe not
http//www.theblaze.com/stories/2012/03/01/feds-decrypt-laptop-of-defendant-ordered-to-turn-over-hard-drive/

Some progresses must have been made since 2010
http//www.theregister.co.uk/2010/06/28/brazil_banker_crypto_lock_out/

jaclaz

 
Posted : 22/01/2013 7:43 pm
(@williamsonn)
Posts: 85
Trusted Member
Topic starter
 

ABSOLUTELY clear now, jaclaz. Thanks wink

 
Posted : 23/01/2013 3:43 am
(@csericks)
Posts: 99
Trusted Member
 

I popped some corn and sat back in my easy chair to read this thread, instead of watching Alan Cumming introduce another fine Masterpiece Theater offering.

Solid performance from jaclaz…though, I must say that I was disappointed that the chase scene and subsequent shootout was cut short. When is the next episode airing? wink

 
Posted : 29/01/2013 7:12 am
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