When you delete something, is it erased forever or is it still there hidden from us?

SSP

Lifer
Oct 11, 1999
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Just wondering cause easy recovery claim that they can recover lost data. If the data is not deleted perminantly, how can they be deleted without any frangments inthe harddrive. Is zero filling the only way? Or is there a beter way to do this. Is it possible to delete the file 1 by 1 if they are still in the drive?

 

Cattlegod

Diamond Member
May 22, 2001
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when you delete a file it marks where the file starts, and where the file ends and says from here to there is free space. it doesn't change the data on the hard drive. if it did change data, it wouldn't make sense, why would you need to? if you are going to overwrite what was there before, it doesn't matter what was there before, so that is why they don't erase the whole file and why they can recover deleted files.
 

SSP

Lifer
Oct 11, 1999
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So this is why zero filling is the only way to clear a drive? It fills everything with zeros which basically over writes the old data?

Intersting. :)
 

mithrandir2001

Diamond Member
May 1, 2001
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Zero filling is a first step, but it still doesn't get rid of the data...a committed slueth can still retrieve the old data with sophisticated tools. You need to "scrub" your hard drive with special data patterns to effectively destroy any old data. I wouldn't worry about it unless you expect the feds to start banging at your front door. In that case, a sledgehammer blow to the hard drive would probably be as effective in data destruction.
 

Derango

Diamond Member
Jan 1, 2002
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Actualy, to completly prevent any type of data recovery, you need to zero fill multiple times. I believe 7 times, although if I'm wrong on the amount, let me know :)
 

Viper GTS

Lifer
Oct 13, 1999
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7 times is DoD standard, apparently.

I believe it's something like:

All zero's
All one's
All zero's
All one's

etc.

Viper GTS
 

SSP

Lifer
Oct 11, 1999
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<< Zero filling is a first step, but it still doesn't get rid of the data...a committed slueth can still retrieve the old data with sophisticated tools. You need to "scrub" your hard drive with special data patterns to effectively destroy any old data. I wouldn't worry about it unless you expect the feds to start banging at your front door. In that case, a sledgehammer blow to the hard drive would probably be as effective in data destruction. >>



Oh oh.. I hear a knock.

How does that "scrub" work? I got a sponge and some pinesol ready. ;)

Wow... 7 times to clean the hard drive.... thats insane. Cool facts. Thanks guys. :)

 

Viper GTS

Lifer
Oct 13, 1999
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<<

<< I thought a disk defrag would do the trick? >>



LOL. :D
>>



Actually, he's not that far from correct.

Defragging will overwrite the blank space with data from another file.

Viper GTS
 

sean2002

Golden Member
Apr 9, 2001
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This is how I destroy data I don't want anyone to see. First I encrypt the file using ABI coder using a 440bit Blowfish encrtption using no english words, different case letters, numbers and !@#$$%^&** all mixed up. Then I use Norton's Wipe info using the goverment wipe (DoD 5220.22-m) twice
 

SSP

Lifer
Oct 11, 1999
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<< This is how I destroy data I don't want anyone to see. First I encrypt the file using ABI coder using a 440bit Blowfish encrtption using no english words, different case letters, numbers and !@#$$%^&** all mixed up. Then I use Norton's Wipe info using the goverment wipe (DoD 5220.22-m) twice >>



Whoah! Dont you think that a little excessive? :Q
 

beat mania

Platinum Member
Jan 23, 2000
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<< I'm waiting for someone to explain the necessity to zero fill multiple times... >>



Because I believe the magnetic strength on that bit is different if it was a 1 and you overwrite it with a 0 and if it was a 0 and you still write a 0. Every time you do it the trace from the previous write gets weaker until it becomes too miniscule to detect (7 times they say (top)) Of course, you can't just use your own computer to look at it.
 

docmanhattan

Golden Member
Jul 31, 2001
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How about a really strong magnet? Would that F* things up enough to prevent it from being recoverable?
 

SSP

Lifer
Oct 11, 1999
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<< Interesting...how do you recover those files? Like just deleted once >>



Use easy recovery from ontrack. It works.

Renob... trying it now. :) thx.