1

Vincent Dupaquis, Michel Douguet:
Randomized modular polynomial reduction method and hardware therefor.
Atmel Rousset S,
Schwegman Lundberg & Woessner P A,
September 28, 2010:
US07805480
(17 worldwide citation)

A cryptographically secure, computer hardware-implemented binary finite-field polynomial modular reduction method estimates and randomizes a polynomial quotient used for computation of a polynomial remainder. The randomizing error injected into the approximate polynomial quotient is limited to a few ...

2

Vincent Dupaquis, Michel Douguet:
Encryption protection method.
Atmel Rousset S,
Schwegman Lundberg & Woessner P A,
December 7, 2010:
US07848515
(14 worldwide citation)

A deterministic blinding method for cipher algorithms that employ key-mixing and substitution (S-box) operations uses a masking table constructed with a true mask and a plurality of dummy masks corresponding to every possible S-box input. Each mask is applied in the key-mixing operation (e.g., bitwi ...

3

Vincent Dupaquis, Michel Douguet:
Digital computation method involving euclidean division.
Atmel Corporation,
Schwegman Lundberg & Woessner P A,
March 2, 2010:
US07672990
(4 worldwide citation)

A computational method for implementation in an electronic digital processing system performs integer division upon very large (multi-word) operands. An approximated reciprocal of the divisor is obtained by extracting the two most significant words of the divisor, adding one to the extracted value a ...

4

Guillaume Pean, Alain Vergnes, Michel Douguet:
Encrypted memory access.
Atmel Corporation,
Fish & Richardson P C,
May 13, 2014:
US08726037
(4 worldwide citation)

Various systems and methods for encrypting data are disclosed. In one aspect, the method includes receiving a memory address and a value to be written in the memory address. The method also includes encrypting the value using the memory address as an initial value for an encryption process. The meth ...

5

Michel Douguet, Vincent Dupaquis:
Key protection mechanism.
Atmel Rousset S,
Schwegman Lundberg & Woessner P A,
October 26, 2010:
US07822207
(3 worldwide citation)

A method of protecting secret key integrity in a hardware cryptographic system includes first obtaining an encryption result and corresponding checksum of known data using the secret key, saving those results, then masking the secret key and storing the masked key. When the masked key is to be used ...

6

Michel Douguet, Vincent Dupaquis:
Elliptic curve point transformations.
Inside Secure,
Panitch Schwarze Belisario & Nadel,
October 15, 2013:
US08559625
(2 worldwide citation)

In an elliptic curve cryptographic system, point coordinates in a first coordinate system are transformed into a second coordinate system. The transformed coordinates are processed by field operations, which have been modified for operating on the transformed point coordinates. In some implementatio ...

7

Michel Douguet, Vincent Dupaquis:
Modular reduction using a special form of the modulus.
Inside Secure,
Fish & Richardson P C,
July 31, 2012:
US08233615
(2 worldwide citation)

A special form of a modulus and a modified Barrett reduction method are used to perform modular arithmetic in a cryptographic system. The modified Barrett reduction is a method of reducing a number modulo another number without the use of any division. By pre-computing static values used in the Barr ...

8

Michel Douguet, Vincent Dupaquis:
Representation change of a point on an elliptic curve.
Inside Secure,
Panitch Schwarze Belisario & Nadel,
December 31, 2013:
US08619977
(2 worldwide citation)

An elliptic curve cryptographic system where point coordinates are transformed from a first coordinate system to a second coordinate system. The transformed coordinates are processed by field operations, which have been modified for operating on the transformed point coordinates. In some implementat ...

9

Michel Douguet, Neil M McKeeney:
Chinese remainder theorem-based computation method for cryptosystems.
Inside Secure,
Schwegman Lundberg & Woessner P A,
October 2, 2012:
US08280041
(2 worldwide citation)

A computer hardware implemented cryptography method computes a modular exponentiation, M :=Cd (mod p·q), upon a message data value C using a Chinese Remainder Theorem (CRT) based technique. To secure against cryptanalysis, the private key moduli p and q are transformed by multiplication with a gener ...

10

Vincent Dupaquis, Michel Douguet:
Randomized modular reduction method and hardware therefor.
Atmel Rousset S,
Schwegman Lundberg & Woessner P A,
October 5, 2010:
US07809133
(1 worldwide citation)

A cryptographically secure, computer hardware-implemented modular reduction method systematically underestimates and randomizes an approximate quotient used for computation of a remainder. The randomizing error injected into the approximate quotient is limited to a few bits, e.g. less than half a wo ...