TAG MIL-BOOK 200 Series manual How is key length related to security?

Models: MIL-BOOK 200 Series

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A: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.

Q:How is key length related to security?

A: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, 240 (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.

Q:Such that X-WallLX-40(DES 40-bit strength) is insecure?

A:Not true. Above explained Secure Key finding process is specifically relating to decrypting software-based encryption. The innovative X-Wallhardware based encryption solution increases the difficulties tremendously as every guess of the Secret Key requires a hardware reset (power on). To break an X-WallLX-40encrypted hard drive, one must process at least 500 billion times (50% of the available key space) reboot. As such, X-Walleven with its DES 40-bit strength will be strong enough against massive computer attacks.

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

A: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.

Q:Why do I need to use the Secure Key?

A:The X-Wall Secure Key covers 5 characters as we set on HDD encryption. It contains the DES/TDES Secret Keythat 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 Secure Key and X-Wall LX comprise an effective user authentication for access control and encryption for data protection. The X-Wall Secure Key serves as user authentication for access control while X-Wall LX encrypts and decrypts.

Q:What happens if my Secure Key is lost or stolen?

Hard Disk Encryption

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TAG MIL-BOOK 200 Series manual How is key length related to security?