Abstract: Transponders in a system execute commands issued by an interrogator. The interrogator sends out interrogation signals, and a transponder answers with a start signal. The interrogator then modifies its interrogation signal and this causes the answering transponder to send an identification signal and the other transponders to be silent for a time period. The interrogator subsequently sends a second modification of the interrogation signal and a command which causes the other transponders to remain silent for a period of time, and the answering transponder to execute the command. Repeated modified interrogation signals and additional commands can be sent so that the other transponders remain silent while the answering transponder executes the commands. After a certain time following the last modified interrogation signal and executed command, the transponders return to the non-silent state. Time is measured by local counters in each transponder.

Abstract: A countermeasure method in an electronic component implementing an elliptical curve based public key cryptography algorithm. A new decryption integer d? is calculated such that the decryption of an encrypted message on the basis of a private key d and the number of points n of an elliptical curve provides the same result with d? as with d, by performing the operation Q=d*P, whereby P is a point of the curve. Four steps are employed in the calculation: 1) a security parameter s is determined, 2) a random number k ranging from 0-2s is drawn, 3) the integer d?=d+k*n is calculated, and 4) Q=d?.P is calculated.

Abstract: A a color ink-jet printer has at least four ink cartridges each containing one basic color selected from among yellow, magenta, cyan and black, and at least one additional cartridge containing a basic pale color ink. A processor receives a printing order containing data concerning the requested color and/or the number and color of the ink droplets to be deposited on one another at a specific location of a selected printing substrate. The processor includes an optimizing mode capable of matching the requested color and/or the required number and color of droplets to be superimposed to obtain a selected color at a given pixel with an equivalent color and/or an equivalent number and/or color of droplets to be superimposed to obtain a substantially equivalent and satisfactory color rendering in conformity with the human eye sensory response. The thus-determined equivalent color and/or the equivalent number and color of droplets to be superimposed is applied to the printer for each printing order received.

Abstract: A graphic printing machine and method for a card-type storage medium employs a jet printing head and a controller to perform ink jet printing on the medium. The invention is useful for printing plastic or cardboard or paper cards.

Abstract: The customization or initialization of the application, for example in a programmable smart card, uses minimum integrated code. A device for preparing customizing or initializing data to be transmitted to the card creates a concatenation of information elements in respective adjacent data blocks in accordance with a convention recognized by a communication device, without explicit field specification. On reception of a data sequence, the card code identifies the information elements according to their size and their position in the flow.

Abstract: Pressure regulation in a liquid reservoir such as an ink of a jet printing head, is obtained by transferring a calibrated gas volume through an auxiliary reservoir, said regulation is being applied to installations manufacturing intelligent portable objects and more particularly to graphic customization stations.

Abstract: A method for, producing contact-free chip card includes embedding metallized bumps of the chip into an antenna as the chip is mounted on the antenna.

Abstract: The invention relates, mainly to a cryptographic process using an elliptic curve represented by means of an equation containing first and second parameters (a, b), a bilinear matching, and calculations in a finite group of integers constructed around at least one first reduction rule reducing each integer to its remainder in a whole division by a first prime number (p) that constitutes a third parameter, the elements of the finite group being in bijection with points selected on the elliptic curve, and the number of which is linked to a fourth parameter (q), where this process uses public and private keys, each of which is represented by a given point of the elliptic curve or by a multiplication factor between two points of this curve. According to the invention, the first reduction rule is the only reduction rule implemented, and the elliptic curve is obtained through a step-by-step construction process, directly allocating to the finite group q*q q-order points in the elliptic curve.

Abstract: The invention relates to a method of masking a plain datum b having n bits. The inventive method is characterised in that a masked datum m is produced using the following masking function: (I), wherein p is a prime number, bi is the bit at position i of plain datum b, and qi is the prime number at position i in a set of prime numbers (q1, . . . , qn) The invention also relates to a method of masking a biometric print, consisting in: determining a set of s real minutiae which are characteristic of the print; mixing and arranging the real minutiae with t false minutiae; and forming a mixed biometric datum b having n=s+1 bits, such that, for any i: bi=1 if position i corresponds to a real minutia, and bi=0 if position i corresponds to a false minutia. The invention can be used to secure a security document such as a bank cheque.

Abstract: In a method for backing up personal data of a wireless communications network subscriber, the data is saved in a mobile communications device and backed up in a server of the network. A first subset of data is prepared from a set to be saved by a SIM card and is transmitted to the server for backing up. In an asynchronous backup mode, after the transmission of a subset of data to be backed up on the server, the backup is delayed for a certain period of time in order to free the mobile device for the user, and the backup is resumed at the end of this period.

Abstract: The invention relates to a device for securing access to a piece of equipment (EQP), comprising an authentication medium (CRD) which uses a reference datum and control means (CTRL) which can be used to verify the consistency between the reference datum and a biometric signature (SGN) obtained from a party requesting access. According to the invention, the reference datum comprises an encrypted version (CRYPT_SGN02) of an authentic biometric signature (SGN02) attributed to the party requesting access, and the aforementioned data consistency is verified by comprising (COMPAR) the biometric signature (SGN) obtained from a party requesting access to an authentic biometric signature (SGN02) resulting from decryption of the encrypted version (CRYPT SGN02) of said signature using a secret key (K).

Abstract: The invention relates to the operational maintenance of an intelligent portable object (1) which is provided with a processing unit (6) having at least two communication and/or feed interfaces either with or without contacts. The method comprises a reinitialization step (MaZ) for the processing unit (6). The method is characterized in that it comprises at least one delay and/or reinitialization simulation step if a communication or application is in the process of being processed by the processing unit. The invention also relates to an associated device.

Abstract: The invention concerns a method solving security problems resulting from the addition of a security circuit to a smart card reading terminal by providing said security circuit with means for counting the number of times the security circuit is activated for certain sensitive operations. When the total of said operations reaches a fixed value, the security circuit is prevented from operating until it is re-initialized again. Optionally, the circuit may have to be replaced by another.

Abstract: The invention relates to a cryptographic method wherein, in order to carry out a fully polynomial division of type Q(x)[U(x)/N(x)], wherein Q(x), N(x) and U(x) are polynomials, respectively a result, dividend and a divider, multiplication of the two polynomials is carried out followed by displacement of the bits of the result of the multiplication. The operation is performed on the body of polynomials Fp[x]. The invention enables more complex operations to be carried out, including modular operations. The invention is an alternative to the Montgomery method and does not need any correction. It is useful, in particular, for cryptographic methods wherein polynomial operations are carried out on the body F2[x]. The invention also relates to an appropriate coprocessor for carrying out the method.

Abstract: In a method of producing a digital certificate, a certificate authority compiles a data set containing a public key and digital data that identifies the owner of the public key and an associated private key, and subsequently signs that data set to produce a digital certificate. The invention, the digital data also includes data that identifies a device for generating the private key and/or storing the private key on a support and/or signing with the private key. The method can be used to produce X509-type digital certificates.

Abstract: A mobile telephone handset includes: a storage support which is secured against fraudulent access and which stores the IMEI of the handset. A connector for a secure electronic module is associated with an operator. A handset operating system controls authentication of the IMEI storage support by a secure electronic module which is connected to the aforementioned connector in order to establish a secure communication channel between the storage support and the module and transmission of the IMEI over the secure channel to the secure electronic module. The arrangement can be used to prevent the dynamic modification of the IMEI during the transmission thereof.

Abstract: The invention relates to a method for countermeasuring in an electronic component while using a public key cryptographic algorithm. The invention involves the use of a public key cryptographic algorithm containing an exponentiation calculation y=gˆd, in which g and y are elements of specified group G noted in a multiplicative manner and d is a predetermined number.

Abstract: A device external to a terminal transmits a specific application identifier and an encrypted first key and number to a first chip card in service in the terminal. In the first card, if the decrypted first number satisfies a first condition, the specific application is called up, application data are read, the data are encrypted using the decrypted first key to transmit them to the external device, and the application is made inoperable. Following replacement of the first card by a second card, the external device transmits the identifier and an encrypted second key and number to the second card. In the latter, if the decrypted second number satisfies a second condition, the encrypted data are transmitted to the second card so that the latter calls up the application, decrypts the encrypted data using the decrypted second key and installs said data.

Abstract: A cryptography method for generating probabilistic digital signatures and/or for a key-exchange a protocol and/or for an encryption algorithm is based on the use of a public key algorithm on abnormal binary elliptic curve, such as a Koblitz curve. A point P (x, y) is selected, and pairs (ki, Pi) are stored with Pi being the point corresponding to the scalar multiplication of the point P by ki. A random variable (k) is generated and a point C is calculated that corresponds to the scalar multiplication of P by k. The generation of the random variable (k) and the calculation of the point C are performed simultaneously.

Abstract: In a method for saving personal data for a subscriber to a wireless communications network, the data is being memorized in a mobile communication station and saved in a network server by means of a first communication channel and in a first saving mode. A determination is made whether the mobile device may establish a second communication channel and/or has an other mode of saving. If so, communication is opened on the second channel and/or according to the other mode, and the data is saved by means of the second communication channel and/or the other mode.