Wiping schemes
Using Delete Files Permanently you can wipe files using any of built-in wiping schemes or you can create your own wiping scheme (wiping pattern) or create wiping schemes based on built-in algorithms to be certain that your confidential files are deleted forever. If necessary, you can easily view, add and modify wiping schemes.
Built-in list of wiping schemes:
- Fast (1 pass)
The fastest wiping scheme. Your data is overwritten with zeroes.
- British HMG IS5 (Baseline) (1 pass)
Your data is overwritten with zeroes with verification.
- Russian GOST P50739-95 (2 passes)
GOST P50739-95 wiping scheme calls for a single pass of zeroes followed by a single pass of random byte.
- British HMG IS5 (Enhanced) (3 passes)
British HMG IS5 (Enhanced) is a three pass overwriting algorithm: first pass - with zeroes, second pass - with ones and the last pass with random bytes (last pass is verified).
- US Army AR380-19 (3 passes)
AR380-19 is a data wiping scheme specified and published by the U.S. Army. AR380-19 is a three pass overwriting algorithm: first pass - with random bytes, second and third passes with certain bytes and compliment (with last pass verification) .
- US Department of Defense DoD 5220.22-M (3 passes)
DoD 5220.22-M is a three pass overwriting algorithm: first pass - with zeroes, second pass - with ones and the last pass with random bytes. With all passes verification.
- the US Department of Defense DoD 5220.22-M (E) (3 passes)
DoD 5220.22-M (E) is a three pass overwriting algorithm: first pass - with certain bytes, second pass - with the complement and the last pass - with random bytes.
- NAVSO P-5239-26 (RLL)
NAVSO P-5239-26 (RLL) is a three pass overwriting algorithm with last pass verification.
- NAVSO P-5239-26 (MFM)
NAVSO P-5239-26 (MFM) is a three pass overwriting algorithm with last pass verification.
- the US Department of Defense DoD 5220.22-M(ECE) (7 passes)
DoD 5220.22-M(ECE) is a seven pass overwriting algorithm: first and second passes - with certain bytes and the compliment, then two passes with a random character, then two passes with a character and its complement and the last pass - with a random character.
- Canadian RCMP TSSIT OPS-II (7 passes)
RCMP TSSIT OPS-II is a seven pass overwriting algorithm with three alternating patterns of zeroes and ones and the last pass - with random character (with last pass verification).
- German VSITR (7 passes)
The German standard calls for each sector to be overwritten with three alternating patterns of zeroes and ones and in the last pass with character.
- Bruce Schneier (7 passes)
The Bruce Schneier wiping algorithm has seven passes: first pass - with ones, the second pass - with zeroes and then five times with random characters.
- Peter Gutmann (35 passes)
Peter Gutmann wiping algorithm has 35 passes.
|
 Note: Unless government strength security is desired, wiping schemes with one, two or three passes are sufficient to completely delete files information.
|
|
How to create your own wiping scheme
You can easily customize wiping process on your computer. Delete Files Permanently includes the Wiping Scheme Editor to add new wiping schemes and view and edit existing ones.
While creating and editing a wiping scheme you can set the number of wiping passes and byte patterns used in every pass.
To add a wiping scheme:
Run Delete Files Permanently Portable
Click the 'Tools' button  in the toolbar.
Select 'Wiping Schemes'.
Click the 'Add' button.
|
Note: You can easily create your own wiping scheme based on built-in wiping schemes. As built-in wiping schemes can't be deleted or modified, you should duplicate the required wiping scheme first using the 'Duplicate' button, then click the 'Modify' button and make necessary changes.
 Learn how to modify a wiping scheme...
|
|
- Enter wiping scheme's name
- to add a new overwrite pass, click the 'Add' button under 'Pass'
In the 'Add/modify pass' window:
• select Byte pattern - select what symbol(s) you want to use for data overwriting:
- select the 'Certain value' option - to use any symbol you want for data overwriting
- select the 'Random' option - if you want to use random bytes for overwriting data on this pass
- select the 'Complement' option - to use the complement to the previous pass value
• select 'Number of byte patterns' - set how many byte patterns you want to use for the wiping pass. You can use up to 5 byte patterns
|
|
Note: you can't use 'Use complement value' for the first pass as there is no previous value
|
|
 Tips:
For your convenience you can enter byte patterns in different formats:
- in binary format
- in symbol format
- in hexadecimal format
|
|
- Verification:
• without verification - overwrite data without verification
• last step - overwrite data and verify last step (pass) only
• verify all steps - Delete Files Permanently overwrites data and verifies each step (pass) if the data was written correctly to the disk
|
Note: If you select the 'Last step' or 'All steps' verification, you should select program actions if verification is failed:
- ask about necessary action if verification failed
- skip current pass
- delete file any way
|
|
Click 'OK'.
How to view a wiping scheme
Click the 'Tools' button in the toolbar.
Select 'Erase Files and Folders'.
Select the wiping scheme you want to view from the drop-down list and click the 'View scheme' button.
How to modify a wiping scheme
|
|
Note: Built-in wiping schemes can't be modified or deleted
|
|
Click the 'Tools' button in the toolbar.
Select 'Wiping Schemes'.
Select the wiping scheme you want to modify and click the 'Modify' button.
Make necessary changes. You can change:
- the number of passes (using the 'Add' or 'Delete' pass buttons);
- change byte patterns and the number of byte patterns for each pass;
- verification mode
|
Note: If you select the 'Last step' or 'All steps' verification, you should select program actions if verification is failed:
- ask about necessary action if verification failed
- skip current pass
- delete file any way
|
|
- modify existing passes (what byte pattern and how many byte patterns are used for data overwriting);
For more convenience you can view and enter byte patterns in different formats:
- in binary format;
- in symbol format;
- in hexadecimal format;
How to delete a wiping scheme
|
|
Note: Built-in wiping schemes can't be modified or deleted
|
|
Click the 'Tools' button in the toolbar.
Select 'Wiping Schemes'.
Select the wiping scheme you want to delete and click the 'Delete' button.
How to duplicate a wiping scheme
Click the 'Tools' button in the toolbar.
Select 'Wiping Schemes'.
Select the wiping scheme you want to delete and click the 'Duplicate' button.
Enter a new wiping scheme name
|
