Cryptography – Particular algorithmic function encoding – Nbs/des algorithm
Reexamination Certificate
2003-09-25
2008-11-18
Nguyen, Minh Dieu (Department: 2137)
Cryptography
Particular algorithmic function encoding
Nbs/des algorithm
C380S028000, C380S042000, C711S113000, C711S118000
Reexamination Certificate
active
07454016
ABSTRACT:
A data encryption system implemented by running on a cache-equipped computer an encryption program including transformation tables each of which contains a predetermined number of entries. All or necessary ones of the transformation tables are loaded into the cache memory before encryption/decryption process. This causes encryption/decryption time to be made substantially equal independently of the number of operation entries for the transformation table. It is very difficult to extract plain texts used to determine a key differential, resulting in difficulties in cryptanalysis.
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Dickstein , Shapiro, LLP.
NEC Corporation
Nguyen Minh Dieu
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