a noob question about NSA (7passes)

[ecw]

what does NSA ( 7passes ) do?

[Tarq57]

It over-writes a file seven times, in effect, erasing (or shredding) it. Such a file is not normally recoverable, if at all. In fact a file overwritten at all is difficult to recover, 3 would be considered pretty secure, 7 very, and there is an overwriting protocol called the Gnutman (named for the Author) which overwrites 35 times, for the truly paranoid.

Just deleting a file merely gets rid of the header information; the remainder of the file is left behind and if not overwritten, can be easily recovered. Overwriting a file takes a bit longer than just deleting it.

(I think NSA stands for No Such Agency..7 overwrites is the protocol they consider adequate to destroy a file.)

[User000]

It over-writes a file seven times, in effect, erasing (or shredding) it. Such a file is not normally recoverable, if at all. In fact a file overwritten at all is difficult to recover, 3 would be considered pretty secure, 7 very, and there is an overwriting protocol called the Gnutman (named for the Author) which overwrites 35 times, for the truly paranoid.

Just deleting a file merely gets rid of the header information; the remainder of the file is left behind and if not overwritten, can be easily recovered. Overwriting a file takes a bit longer than just deleting it.

(I think NSA stands for No Such Agency..7 overwrites is the protocol they consider adequate to destroy a file.)

 

nsa is some sort of gov orgazation from eraser hompage: Other methods include the one defined in the National Industrial Security Program Operating Manual of the US Department of Defence and overwriting with pseudorandom data.