Patents by Inventor Regis Bevan

Regis Bevan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • PROTECTING MODULAR EXPONENTIATION IN CRYPTOGRAPHIC OPERATIONS
    Publication number: 20130279692
    Abstract: The present invention proposes a method for executing a blinded modular exponentiation, based on a window method with a window size of k bits so using 2k pre-calculated variables (Yi=Xi mod N for i=0 to 2k?1), on input data X of n bits to obtain output data S of n bits, S=Xd mod N, where d is the exponent of size m bits and N is the modulus of n bits, comprising the steps of: •blinding the pre-calculated variables by a blinding value Bi being a pseudo-random variable of the size of the modulus (n bits) and lower than the modulus (Yj=Yi×B1 mod N for i=0 to 2k?1) •executing the modular exponentiation with the blinded pre-calculated variables, to obtain an intermediate result (A), •unblinding the intermediate result by a unblinding value C1=(B1g)?1 mod N where g equals the concatenation of m/k times the value “1” coded on k bits, to obtain the output data S.
    Type: Application
    Filed: September 29, 2011
    Publication date: October 24, 2013
    Applicant: NAGRAVISION S.A.
    Inventor: Regis Bevan
  • Secure data processing method based particularly on a cryptographic algorithm
    Patent number: 8386791
    Abstract: The invention relates to a secure data processing method comprising the steps of generating (E204; E304) a first random value (A1); executing (E206; E306) a first cryptographic algorithm (FK) using the first random value (A1); generating (E208; E308) a second random value (A2); executing (E210; E310) a second cryptographic algorithm (FK; GK) using the second random value (A2); and generating a result (V) to verify that the first algorithm (FK) was properly executed.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: February 26, 2013
    Assignee: Oberthur Technologies
    Inventors: Régis Bevan, Christophe Giraud, Hugues Thiebeauld De La Crouee
  • Secure data processing method based particularly on a cryptographic algorithm
    Publication number: 20070177720
    Abstract: The invention relates to a secure data processing method comprising the steps of generating (E204; E304) a first random value (A1); executing (E206; E306) a first cryptographic algorithm (FK) using the first random value (A1); generating (E208; E308) a second random value (A2); executing (E210; E310) a second cryptographic algorithm (FK; GK) using the second random value (A2); and generating a result (V) to verify that the first algorithm (FK) was properly executed.
    Type: Application
    Filed: March 7, 2005
    Publication date: August 2, 2007
    Applicant: OBERTHUR CARD SYSTEMS SA
    Inventors: Regis Bevan, Christophe Giraud, Hugues Thiebeauld De La Crouee