HP LaserJet Enterprise - Hard Disk Security Features available in HP FutureSmart firmware printers

7 Public
Appendix A: Secure Erase Data Overwrite and Specifications
Normally when a file is deleted from a HDD, the filename entry is erased from the disk’s file allocation
table, removing the file’s presence. The file’s data still exists in the disk’s individual sectors and is
overwritten only when that sector is allocated for a different file.
HP Secure Erase technology overwrites a deleted file’s data from the individual sectors with random data
using either a one pass or three pass overwrite, which conform to current US Government specifications.
Note: See the Government Erase Specifications section for further information
To enable Secure Erase using data overwrite, select the following options for “File Erase Mode” when
available:
 Non-secure Fast Erase mode: Performs standard file system delete only (does not overwrite file data)
 Secure Fast Erase mode: Performs a one pass overwrite of all data
 Secure Sanitizing Erase mode: Performs a three pass overwrite of all data
Note: The system default is Non-Secure Fast Erase mode. Secure Fast Erase mode is recommended for best
overwrite system performance.
Overwrite Specifications
Secure Fast Erase mode follows the National Institute of Standards and Technology Special Publication
800-88, Guidelines for Media Sanitization.
For Secure Fast Erase, each deleted file’s data is overwritten once with:
 the hexadecimal character 0x48.
Secure Sanitizing Erase mode follows the U.S. Department of Defense 5220-22.M specification using a
succession of multiple data overwrites.
For Secure Sanitizing Erase, each deleted file is overwritten with:
 the fixed character pattern (binary 01001000).
 the complement of the fixed character pattern (binary 10110111).
 a random character:
o A 32k byte buffer of random characters is generated for each file delete operation using the
device’s unique uptime as the seed.
o Each byte of file data uses a unique random character from the buffer.
o The random character buffer is reused up to 32 times, and then regenerated using new random
data.
To ensure successful completion of each overwrite operation, each overwritten byte is verified.
Note: NIST SP-800-88 “Guidelines for Media Sanitization” (Sept 2006) supersedes the US DOD 5220-2.M
(1997 edition) specification.