User's Manual

148 Copyright © Acronis, Inc., 2000-2009
No. Algorithm (writing method) Passes Record
verification.
2. United States: NAVSO P-
5239-26 (RLL)
4
1
st
pass – 0x01 to all sectors, 2 – 0x27FFFFFF, 3 –
random symbol sequences, 4 – verification.
3. United States: NAVSO P-
5239-26 (MFM)
4
1
st
pass – 0x01 to all sectors, 2 – 0x7FFFFFFF, 3 –
random symbol sequences, 4 – verification.
4. German: VSITR 7
1
st
– 6
th
– alternate sequences of: 0x00 and 0xFF; 7
th
– 0xAA; i.e. 0x00, 0xFF, 0x00, 0xFF, 0x00, 0xFF, 0xAA.
5. Russian: GOST P50739-95 1 Logical zeros (0x00 numbers) to each byte of each
sector for 6
th
to 4
th
security level systems.
Randomly selected symbols (numbers) to each byte
of each sector for 3
rd
to 1
st
security level systems.
6. Peter Gutmann's method 35 Peter Gutmann's method is very sophisticated. It's
based on his theory of hard disk information wiping
(see Secure Deletion of Data from Magnetic and
Solid-State Memory).
7. Bruce Schneier's method 7 Bruce Schneier offers a seven-pass overwriting
method in his Applied Cryptography book. 1
st
pass –
0xFF, 2
nd
pass – 0x00, and then five times with a
cryptographically secure pseudo-random sequence.
8. Fast 1 Logical zeros (0x00 numbers) to all sectors to wipe.