Abstract: A method of transmitting information between a plurality of radioelectric stations and an associated transmission network are disclosed. In one aspect, the method transmits information between radioelectric stations, each station including a transmitter and a receiver, the information including NbMot words of data, NbMot being an integer >1.

Abstract: A method of transmitting information between a plurality of radioelectric stations and an associated transmission network are disclosed. In one aspect, the method transmits information between radioelectric stations, each station including a transmitter and a receiver, the information including NbMot words of data, NbMot being an integer >1.

Abstract: A technique for secure delegation of calculation of a value f(X,Y) of a bilinear application in a computational server. The technique comprises selection of two secret parameters a and b; calculation of the numbers Xa and Yb; supply of the two numbers Xa and Yb to the computational server; calculation of f(Xa, Yb) by said server; receipt of the value of f(Xa,Yb) from the server; extraction of the abth root of f(Xa,Yb).

Abstract: Method for generating pseudo-random bit strings in a system in which the data interchanges between a first user and a second user are protected, characterized in that it comprises at least the following steps: using an application fk of output size n bits, determining a value x and, from this value x and by applying the application fk, generating t values vi, from the t values vi and, from u*t coefficients, determining u blocks Si containing pseudo-random characters. Applicable to the coding or authentication domain.

Abstract: A method and device for performing a cryptographic operation by a device controlled by a security application executed outside thereof in which a cryptographic value (y) is produced a calculation comprising at least one multiplication between first and second factors containing a security key (s) associated with the device and a challenge number (c) provided by the security application. The first multiplication factor comprises a determined number of bits (L) in a binary representation and the second factor is constrained in such a way that it comprises, in a binary representation, several bits at 1 with a sequence of at least L?1 bits at 0 between each pair of consecutive bits to 1 while the multiplication is carried out by assembling the binary versions of the first factor shifted according to positions of the bits at 1 of the second factor, respectively.

Abstract: A method and device for performing a cryptographic operation by a device controlled by a security application executed outside thereof in which a cryptographic value (y) is produced a calculation comprising at least one multiplication between first and second factors containing a security key (s) associated with the device and a challenge number (c) provided by the security application. The first multiplication factor comprises a determined number of bits (L) in a binary representation and the second factor is constrained in such a way that it comprises, in a binary representation, several bits at 1 with a sequence of at least L?1 bits at 0 between each pair of consecutive bits to 1 while the multiplication is carried out by assembling the binary versions of the first factor shifted according to positions of the bits at 1 of the second factor, respectively.

Abstract: A technique for secure delegation of calculation of a value f(X,Y) of a bilinear application in a computational server. The technique comprises: selection of two secret parameters a and b; calculation of the numbers Xa and Yb; supply of the two numbers Xa and Yb to the computational server; calculation of f(Xa,Yb) by said server; receipt of the value of f(Xa,Yb) from the server; extraction of the abth root of f(Xa,Yb).