Acronis privacy expert suite 8.0 User Manual

Hard Disk Wiping methods

Copyright © Acronis, Inc., 2000-2005 

69

The table below briefly describes information wiping methods used by Acronis. 
Each description features the number of hard disk sector passes along with the 
number(s) written to each sector byte. 

NN Algorithm 

(writing 

method) 

Passes Record 

1. United 

States 

Department of 
Defense 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. 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 

http://www.cs.auckland.ac.nz/~pgut001
/pubs/secure_del.html

). 

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.