1.2 Wiping Confidential Data from Unoccupied Disk's Space

You may have confidential data on your hard drive in spaces where data may have been stored temporarily.

You may also have deleted files by using the Windows Recycle Bin and then emptying it. While you are still using your local hard drive, there may be confidential information available in these unoccupied spaces.

Wiping the logical drive's deleted data does not delete existing files and folders. It processes all unoccupied drive space so that recovery of previously deleted files becomes impossible.

Installed applications and existing data are not touched by this process. When you wipe unoccupied drive space, the process is run from the bootable CD/DVD operating system. As a result, the wipe or erase process uses an operating system that is outside the local hard drive and is not impeded by Windows system caching. This means that deleted Windows system records can be wiped clean.

KillDisk wipes unused data residue from file slack space, unused sectors, and unused space in MTF records or directory records.

Wiping drive space can take a long time, so do this when the system is not being otherwise utilized. For example, this can be done overnight.

Wipe Algorithms

The process of deleting files does not eliminate them from the hard drive. Unwanted information may still be left available for recovery on the computer. A majority of software that advertises itself as performing reliable deletions simply wipes out free clusters. Deleted information may be kept in additional areas of a drive. KillDisk therefore offers extra steps to ensure secure deletion.

KillDisk Wipe Algorithms

Specifics of Wiping Algorithms for Different File Systems

  1. Wiping NTFS
  2. Wipe FAT/FAT32/exFAT
  3. Wipe HFS+
  4. Wiping Ext2fs/Ext3fs/Ext4fs

Wiping File Slack Space

This relates to any regular files located on any file system. Free space to be wiped is found in the "tail" end of a file because disk space is usually allocated in 4 KB clusters. Most files have sizes that are not 4KB increments and thus have slack space at their end.
Wipe Algorithms

Open Contents

  1. Product Overview
    1. Erasing Confidential Data
      1. Advanced Data Recovery Systems
      2. International Standards in Data Removal
    2. Wiping Confidential Data from Unoccupied Drive Space
      1. Wiping NTFS
      2. Wipe FAT
      3. Wipe HFS+
      4. Wiping Ext2fs/Ext3fs/Ext4fs
  2. System Requirements for DOS and Windows versions
    1. Personal Computer
    2. Drive Storage System
    3. Other Requirements
    4. Active@ KillDisk for Hard Drives Version
  3. Running Active@ KillDisk for DOS
    1. Preparing a DOS-Bootable floppy,USB
      1. System Formatting
      2. Copying Active@ KillDisk to a floppy, USB
      3. One-Step Method
    2. Preparing a Bootable CD
    3. Modes of Operation
      1. Interactive Mode
        1. Erase Data from a Device
        2. Wiping the Data
      2. DOS Command Line Mode
      3. Autoexecute Mode
    4. Erasing or Wiping Logical Drives (Partitions)
    5. Erase Operation Complete
  4. Running Active@ KillDisk for Windows
    1. Active@ Boot Disk Creator
    2. Modes of Operation
    3. Command Line Mode
    4. Erasing or Wiping Logical Drives (Partitions)
    5. Erase Data from a Logical Drive
    6. Wipe Data from a Logical Drive
    7. Erase or Wipe Operation Complete
  5. Common Questions
    1. How does the licensing work?
    2. How is the data erased?
    3. What is the difference between the Site and Enterprise license?
    4. Which operating systems are supported by Active@ KillDisk?
    5. Is Active@ KillDisk compatible with Macintosh computers?
    6. What to do if I cannot boot from a floppy (USB)?
    7. Will I be able to use my Hard Disk Drive after Active@ KillDisk erase operation?
  6. Descriptions of Erase/Wipe Parameters
    1. Erase/Wipe Methods
      1. One Pass Zeros or One Pass Random
      2. User Defined
      3. US DoD 5220.22-M
      4. US DoD 5220.22-M (ECE)
      5. German VSITR
      6. Russian GOST p50739-95
      7. Canadian OPS-II
      8. HMG IS5 Baseline
      9. HMG IS5 Enhanced
      10. US Army AR380-19
      11. US Air Force 5020
      12. Navso P-5329-26 RL
      13. Navso P-5329-26 MFM
      14. NCSC-TG-025
      15. Bruce Schneier
      16. Gutmann
    2. Other Parameters
      1. Verification
      2. Retry Attempts
      3. Ignore Errors
      4. Clear Log File before Start
      5. Skip Confirmation
      6. Wipe out Deleted/Unused data
    3. Glossary of Terms

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