Lgorithms used by, Cronis, Rive – Acronis Drive Cleanser 6.0 - User Guide User Manual
Page 31: Leanser, A.2 algorithms used by acronis drivecleanser, German: vsitr 7, P. gutmann’s algorithm 35, B. schneier’s algorithm 7, Fast 1
types of hard disks. This knowledge speaks to the necessity of complex multipass
algorithms to guarantee information wiping.
The detailed theory of guaranteed information wiping is described in an
article of Peter Gutmann, please see:
A.2 Algorithms
used
by
Acronis DriveCleanser
The table below briefly describes information wiping algorithms used by
Acronis DriveCleanser. Each description features the number of hard disk
sector passes along with number(s) written to each sector byte.
The description of built-in information wiping algorithms
NN
Algorithm (writing method)
Passes
Record
1.
American: DoD
5220.22-M
4
1
st
pass – randomly selected symbols to
each byte of each sector, 2 –
complementary to written during the 1
st
pass; 3 – random symbols again; 4 – writing
verification.
2.
American NAVSO P-
5239-26 (RLL)
4
1
st
pass – 0x01 to all sectors, 2 -
0x27FFFFFF, 3 – random symbol sequences,
4 – verification.
3.
American 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.
P. Gutmann’s
algorithm
35
Peter Gutmann’s algorithm is very
sophisticated. It’s based on his theory of
hard disk information wiping (see
).
7.
B. Schneier’s algorithm 7
Bruce Schneier offers seven pass overwriting
algorithm in his Applied Cryptography book.
1
st
pass – 0xFF, 2
st
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.
30
Appendix A : Hard Disk Wiping algorithms