Abstract:
An asymmetrical cryptographic method of protecting an electronic chip against fraud in transactions between the electronic chip and an application, involving calculating an authentication value V from input parameters in the electronic chip. The chip produces a pseudo-random number r specific to the transaction by means of a serial pseudo-random generator included in the chip. The chip sends the application a parameter x calculated by the application prior to the transaction, linked to the random number r by a mathematical relationship, and stored in a data memory of the chip. The chip calculates a parameter y constituting the whole or a portion of the authentication value V by means of a serial function whose input parameters are at least the random number r specific to the transaction and a private key s belonging to an asymmetrical pair of keys. The chip sends the authentication value V to the application, and the application verifies the authentication value V by means of a verification function whose input parameters consist exclusively of public parameters including at least the public key p.
Abstract:
An optical fiber distribution frame including a first cross-connection panel (B1) and a second cross-connection panel (B2) facing each other, and a first support (7) in each panel for connection modules (12) thereof. Each module on the first panel is adapted to be connected to one end of an optical fiber (R) of a first group, each module on the second panel is adapted to be connected to one end of an optical fiber (E) of a second group, and an optical fiber of the first group is adapted to be connected to an optical fiber of the second group by a jumper fiber (FL) which has two ends (e1, 20; e2, 20) respectively received in a port of one of the modules on the first panel and in a port of one of the modules on the second panel. The first and second panels each include a second connection module support (7), with said second supports cooperating with each other to form a stowage area for jumper fibers (FL) that are not in use and awaiting connection. The jumper fibers are automatically connected or disconnected by a device (14).
Abstract:
In order to apply an electronic signature from a client station having authentication resources at a server, the following steps are carried out: the client station is authenticated at the server, thus establishing an authenticated communication channel; a private key/public key pair is generated at the client station; a signature certificate request generated by means of at least the public key is transmitted from the client station to the server via the authenticated channel; a signature certificate obtained in response to the request is returned via the authenticated channel; this certificate is verified at the client station; an electronic signature is calculated at the client station by means of the private key, after which this private key is destroyed; and the calculated signature is formatted with the aid of the signature certificate received via the authenticated channel.
Abstract:
A method for managing interactions between at least one peripheral command device and at least one multimedia application exploiting the standard MPEG-4. A peripheral command device delivers digital signals as a function of actions of one or more users comprising: constructing a digital sequence having the form of a BIFS node (Binary Form for Scenes in accordance with the standard MPEG-4), a node comprising at least one field defining a type and a number of interaction data to be applied to objects of a scene.
Abstract:
The invention relates in particular to a method of scrambling a video signal using an encryption key for controlling access to audiovisual information. The video signal is scrambled by applying a tattooing function to the video signal by using a marking key derived from the encryption key, the tattooing function including a parameter for regulating the amplitude of tattooing so as to enable the visibility of the tattooing in the video signal to be adjusted. The invention also provides a dual unscrambling method, and a system, an encoder, a decoder, a broadcast server, and a data medium for implementing said methods.
Abstract:
Method for optimal estimation of a propagation channel based solely on pilot symbols. A base of natural vectors is formed using the correlation matrix of the channel observed solely at the positions of the pilot symbols. Channel representation is broken down in this base. The base vectors are extended to the data symbols, which allows optimal interpolation of channel estimation to the data symbols. Application to OFDM, TDMA and CDMA systems.
Abstract:
A half-wave printed nullpatchnull antenna includes, symmetrically with respect to a plane of symmetry of the antenna perpendicular to faces of the antenna, a dielectric substrate and two conductive layers on respective faces of the substrate. One face of the substrate includes a raised portion extending lengthwise of the plane of symmetry and one of the conductive layers extends over and along said raised portion. Consequently, the antenna has a small size, combined with a more open radiation diagram. The antenna includes only one raised portion for linear polarization, or two raised portions or a raised portion with axial symmetry for crossed polarizations.
Abstract:
A method and a kiosk for managing access to goods and services available via a computer network. A list of identifiers is created. Each identifier is associated with at least one service of a merchant. Tickets are distributed to customers. Access to a service is authorized upon recognition of an identifier on a ticket. The kiosk comprises a generator for generating a list of identifiers, a supervisor which associates an identifier with at least one service of a merchant, a data base of tickets to which the identifier has been applied, and a controller for checking the identifier.
Abstract:
A method is provided to share a content stored on a secured server. The content is associated to a first electronic device and encrypted using a public key of the first electronic device. The secured server stores a first re-encryption key from the first electronic device to a second electronic device. The method is implemented by the secured server and includes the steps of determining association of the content with the second electronic device, re-encrypting the content using the first re-encryption key, sending the content to the second electronic device for encryption using a second device public key and storing the encrypted content received from the second electronic device in association with the second electronic device.
Abstract:
The present method and system implements a method for presenting notifications on an electronic device partitioned into two or more distinct instances, each instance being aware of separate sets of events associated to applications running in that instance. The method includes collecting for each instance the notifications corresponding to the separate sets of events, rendering in the active instance the active instance notifications using a first display mode, while rendering the other instance notifications using a second display mode.