Getac M220 Operation Manual Download

Page: 156 / 157

Hard Disk Encryption

C-3

DES (Data Encryption Standard) was originally introduced by NSA (National
Security Agency) and IBM and has since become a Federal data encryption
standard as defined in FIPS 46-3 (Federal Information Processing Standard).
DES works on 64-bit data segments with a 64-bit key of which 8 bits provide
parity, resulting in a 56-bit effective length. A variant on DES is TDES, in which
the plain text is processed three times with two or three different DES secret
keys. With two encryption keys used, the result is an encryption equivalent to
using a 112-bit (128-bit) key. With three keys, the result is an encryption
equivalent to using a 168-bit (192-bit) key. In practice with a 128-bit TDES, the
plain text is encrypted with the first key, decrypted with the second key, and
then encrypted again with the first key.

How is key length related to security?

In general, a larger key length creates a stronger cipher, which means an
eavesdropper must spend more time and resources to find the decryption key.
For instance, 2

(a DES 40-bit strength) represent a key space of

1,099,511,627,776 possible combinations. While this number seems
impressive, it is definitely feasible for a microprocessor or a specially designed
ASIC to perform the huge number of calculations necessary to derive the key.
Thus a 40-bit length cipher offers a bare minimum protection for your
confidentiality and privacy. Fortunately the “work factor” increases exponentially
as we increase the key length.

Such that X-Wall LX-40 (DES 40-bit strength) is insecret?

Not true. Above explained

Secret Key

finding process is specifically relating to

decrypting software-based encryption. The innovative

X-Wall

hardware based

encryption solution increases the difficulties tremendously as every guess of the
S

ecret Key

requires a hardware reset (power on). To break an

X-Wall LX-40

encrypted hard drive, one must process at least 500 billion times (50% of the
available key space) reboot. As such,

X-Wall

even with its DES 40-bit strength

will be strong enough against massive computer attacks.

How would I make sure the security offered by X-Wall LX is solid?

The DES/TDES hardware engine that

X-Wall LX

utilized has been certified by the

NIST (National Institute of Standards and Technology) and CSE (The Canadian
Security Establishment)

, for which the certificates can be reviewed on NIST web

links: http://csrc.nist.gov/cryptval/des/desval.html &
http://csrc.nist.gov/cryptval/des/tripledesval.html. These hardware algorithms are
certified to provide reliable security; at full strength it is nearly impossible to access the
encrypted data by guessing or deriving the right DES/TDES Key. Because everything
on the disk is encrypted, your data is safe even if attackers try to boot from their own
disk, or to move your disk to an unprotected machine.

Why do I need to use the Secret Key?

The

X-Wall Secret Key covers 5 characters as we set on HDD encryption. It

contains the

DES/TDES

“Secret Key”

that is used by

X-Wall LX

to encrypt or

decrypt data. Without the key, the protected disk drive cannot be booted and
there is no access into the PC. Together the

X-Wall Secret Key

and