Global Patent Index - EP 1016240 A1

EP 1016240 A1 2000-07-05 - IMPROVED BLOCK CIPHER METHOD

Title (en)

IMPROVED BLOCK CIPHER METHOD

Title (de)

VERFAHREN ZUR VERBESSERTEN BLOCKVERSCHLÜSSELUNG

Title (fr)

PROCEDE DE CHIFFREMENT BLOC AMELIORE

Publication

EP 1016240 A1 (EN)

Application

EP 98949350 A

Priority

  • US 9819255 W
  • US 5914297 P
  • US 6299297 P
  • US 6433197 P

Abstract (en)

[origin: WO9914889A1] A data encryption system for encrypting an n-bit block (110) of input in a plurality of rounds is presented, where n is preferably 128 bits or more. The data encryption system includes a computing unit for the execution of each round; memory for storing and loading segments by predetermined numbers of bits preferably to achieve active and effective fixed rotation; a linear combination function (132) which provides new one-to-one round segments using a round operator generally from one algebraic group to combine two different one-to-one round segments taken from one-to-one round segment set; and a nonlinear function which affects a one-to-one round segment from a particular one-to-one round segment set based on a value which depends on a preselected number of bits in a preselected location from a different one-to-one round segment from the same one-to-one round segment set. The nonlinear function is a variable rotation function or an s-box. A subkey (130) combining function is generally employed in each round to provide new round segments by combining a round segment typically linearly with a subkey segment.

IPC 1-7 (main, further and additional classification)

H04L 9/28

IPC 8 full level (invention and additional information)

H04L 9/06 (2006.01)

CPC (invention and additional information)

H04L 9/0625 (2013.01); H04L 2209/046 (2013.01); H04L 2209/125 (2013.01); H04L 2209/24 (2013.01); H04L 2209/38 (2013.01)

Citation (search report)

See references of WO 9914889A1

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

EPO simple patent family

WO 9914889 A1 19990325; AU 9569098 A 19990405; EP 1016240 A1 20000705

INPADOC legal status


2004-01-07 [18W] WITHDRAWN

- Effective date: 20031031

2000-07-05 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20000301

2000-07-05 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE