Cryptography – Key management
Reexamination Certificate
2007-08-14
2007-08-14
Moise, Emmanuel L. (Department: 2137)
Cryptography
Key management
C380S029000, C380S037000
Reexamination Certificate
active
10164846
ABSTRACT:
A key scheduler for encryption/decryption produces a new ciphering key by a key expansion process or recovers a previous ciphering key by an inverse expansion process. The key scheduler includes a set of adders and transformation circuitry. Each of adders receives a portion of a round key value as its first input. Some of the adders receive either a portion of the round key value or the output of some of the adders, as its second input, be control of arbitration devices. One adder receives as its second input an output from the transformation circuitry, which output is selected by an arbitration device from either a portion of the round key value or an output of an adder. The selection done by the arbitration devices depending on whether the process desired is the key expansion or inverse expansion.
REFERENCES:
patent: 6819764 (2004-11-01), Shimizu et al.
patent: 6931127 (2005-08-01), Lim
patent: 6937727 (2005-08-01), Yup et al.
patent: 2002/0097868 (2002-07-01), Watanabe et al.
patent: 2003/0053623 (2003-03-01), McCanny et al.
patent: 2003/0068036 (2003-04-01), Macchetti et al.
patent: 2003/0099352 (2003-05-01), Lu et al.
patent: 2003/0198345 (2003-10-01), Van Buer
patent: 2003/0202658 (2003-10-01), Verbauwhede
Gergiso Techane J.
Moise Emmanuel L.
Winbond Electronics Corporation
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