ok i have a few questions about dats recovery, i heard the only way you can stop someone from recovering something in your computer is overwriting it with data atleast 30 times? Is this true? :confused:
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ok i have a few questions about dats recovery, i heard the only way you can stop someone from recovering something in your computer is overwriting it with data atleast 30 times? Is this true? :confused:
Data is kept on your hard drive until you overwrite it but I have never heard of needing to overwrite at least 30 times.Say you have a 4 gig hard drive and it is filled to the max.You delete all of it.It would still be on the drive until you overwrited it but if you had to overwrite it 30 times you would have way to much data that the drive couldnt hold.I couldnt explain that very well.
Actually, even after data has been overwritten, it is often recoverable for those with sufficient resources, i.e. government agencies, corporations, etc. Here is some info from data recovery specialists in the UK,
<quote>
Data recovery when the required data has been overwritten
Accidentally ghosting an image over the top of valuable data is a very common form of data loss; it's also a technique used by disgruntled employees and criminals who wish to cover their tracks. By physically overwriting valuable data with other 'junk' data, you would think that the original data would be unrecoverable... You'd be wrong. The Data Clinic are able to recover original data that has been overwritten multiple times.
</quote>
taken from this site.
http://www.dataclinic.co.uk/data-recovery.htm
Overwriting data multiple times decreases the chances for recovery. I don't know about 30 times, but I do remember reading about a technique that can be used to get some(not all usually) data back after being overwritten 7 times. The issue is that a hard drive has a physical memory(writing a positive charge over a negative charge is not always perfect, the material "remembers" previous settings by not having the full charge, or something like that), seperate from the magnetic memory you use to store data. This is not(to my knowledge) a design feature, but more a feature of the physical properties of the materials used.
IchNiSan
As far as overwriting data and number of wipes. Read this paper by Peter Gutmann. It's very interesting to say the least.
http://mirrors.sunsite.dk/cryptoarch...ecure_del.html
This deals with secure deletion etc...
Thanks for that link {P2P}
I did find it interesting and informative
regards
mike
take a look through the archives on this topic. there was a thread a week or two ago where they talked about how many times you needed to do it. One poster said they saw an article where data was succesfully read after 27 rewrites.
I suppose it all boils down to cost vs. how bad you want the data. I have heard of cases that elctron microscopes have been used to examine data bits in the sectors. So if it's a billion dollar corperation or the government after several million in secrets. It could be justified. If it's someone playing on ebay on company. Get a key logger, catch them and fire them. I read an article were in Sweden they recovered data from a physicaly damaged HDD. It was burned and broken. So it all depends on how bad you want it and how much you are willing to spend. Thats why I use a second encrypted drive and put sensitive files on it and only work with them on it. Thats still not foolproof. As I said. If someone has the money and wants your data enough. They can get it.
if your worried about some secret government agency trying to get incrominating evidence from your computer. then you need to do what i do.
Use a remavable hard drive, and then when the agency come knocking on your door, just pull it out and dump it in the bucket full of battery acid nicely stashed beneath your desk :)
thanks guys thats really helpful
i have another thing to ask would it be un recoverable if you just took a magnet to the screen? (and no i dont care about doing all of this stuff i was just curious and i wanted to learn more)
That would just mess up your monitor... not the data on your hard drive....Quote:
i have another thing to ask would it be un recoverable if you just took a magnet to the screen?
"Get real. You are an idiot. You know the HDD is in the case. Stop trying to get attention......... " didnt know that sorry...