Abstract: Motor vehicle comprising a drive system arranged in a compartment at the front of a vehicle, a cradle (2) comprising a platform (4) fastened in this compartment in the region of a floor of the vehicle, an anti-roll bar (10) fastened in the vertical direction above the platform (4), and an impact device (30) fastened to a front edge (20) of the platform (4), behind an impact block fastened to a powertrain of this vehicle, in order, in the event of a recoil of this powertrain, to allow the impact block to bear on the impact device (30), which deforms, the impact device (30) comprising an upper part projecting above the platform (4), which, in the event of a large deformation, bears on the anti-roll bar (10).

Abstract: A connecting module for connecting seismic equipment towed in water, includes a housing having first and second ends opposite to each other, a removable connecting part removably attached to the first end of the housing, an integral connecting part integrally made with the housing at the second end, the integral connecting part having a bore, and one or more pins configured to enter from an outside of the integral connecting part into the bore. An end of the one or more pins has a conical surface that is configured to transfer a radial force FR applied to the one or more pins, as a longitudinal force FL to an electrical insert to be placed in the bore.

Abstract: A method enabling a personal computer to be authenticated by a server is provided. The method comprises the step, which includes for the user in launching the execution of a log-on procedure software, introducing personal identifiers providing access to a signature private key for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module, a public exponent and at least a pair of ephemeral pubic numbers and ephemeral private numbers related by a generic equation of the type: G=Qv (mod n) or G×Qv=1 (mod n), an ephemeral certificate linking, by means of said signature private key, Id and public ephemeral module. The public ephemeral module is of reduced size relative to the signature private key.

Abstract: A cryptography method involving a keyholder having a number m?1 of private keys Q1, Q2, . . . , Qm and respective public keys G1, G2, . . . , Gm, each pair of keys (Qi, Gi) (where i=1, . . . , m) satisfying either the relationship G1=Qiv mod n or the relationship Gi×Qiv=1 mod n, where n is a public integer equal to the product of f (where f>1) private prime factors p1, . . . , pf, at least two of which are separate, and the exponent v is a public integer equal to a power of 2. Disclosed is what mathematical structure may be imparted to the public keys for it to be impossible to calculate said private keys from said public parameters in a reasonable time unless said prime factors are known. Devices adapted to implement the method are also disclosed.

Abstract: A method enabling a personal computer to be authenticated by a server is provided. The method comprises the step, which includes for the user in launching the execution of a log-on procedure software, introducing personal identifiers providing access to a signature private key for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module, a public exponent and at least a pair of ephemeral pubic numbers and ephemeral private numbers related by a generic equation of the type: G=Qv (mod n) or G×Qv=1 (mod n), an ephemeral certificate linking, by means of said signature private key, Id and public ephemeral module. The public ephemeral module is of reduced size relative to the signature private key.

Abstract: A method for enabling a personal computer to be authenticated by a server is provided. The method comprises the step, which includes for the user in launching the execution of a log-on procedure software, introducing personal identifiers providing access to a signature private key for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module, a public exponent and at least a pair of ephemeral pubic numbers and ephemeral private numbers related by a generic equation of the type: Gi?Qiv (mod n) or Gi·Qiv?1 (mod n), an ephemeral certificate linking, by means of said signature private key, Id and public ephemeral module. The public ephemeral module is of reduced size relative to the signature private key.

Abstract: Proof is established by means of the following parameters: m pairs of private values Q1 and public values G1 m>1, a public module n made of the product of f first factors pj, f>2, a public exponent v, linked to each other by relations of the type: G1.Qiv=1 mod n or G1=Q1v mod n. Said exponent v is such that v=2k where k>1 is a security parameter. Public value G1 is the square g12 of a base number gi that is lower than f first factors pj, so that the two equations: x2=gi mod n and x2=?g1 mod n do not have a solution in x in the ring of the modulo n integers and such that the equation xv=g12 mod n has solutions in x in the ring of the modulus n integers.

Abstract: The proof is provided by means of the following parameters: a public module n formed by the product of f prime factors pi, f>2; a public superscript v; m base numbers gi, m>1. The base numbers gi are such that the two equations: x2?gi mod n and x2??gi mod n cannot de solved in x in the ring of integers modulo n, and such that the equation xv?gi2 mod n can be solved in x in the ring of integers modulo n in the case where the public superscript v is in the form v=2k, wherein k is a security parameter.

Abstract: A cryptography method involving a keyholder having a number m?1 of private keys Q1, Q2, . . . , Qm and respective public keys G1, G2, . . . , Gm, each pair of keys (Qi, Gi) (where i=1, . . . , m) satisfying either the relationship Gi=Qiv mod n or the relationship Gi×Qiv=1 mod n, where n is a public integer equal to the product of f (where f>1) private prime factors p1, . . . , pf, at least two of which are separate, and the exponent v is a public integer equal to a power of 2. Disclosed is what mathematical structure may be imparted to the public keys for it to be impossible to calculate said private keys from said public parameters in a reasonable time unless said prime factors are known. Devices adapted to implement the method are also disclosed.

Abstract: The invention concerns a method whereby the proof is established by: m(?1) pairs of private Qi and public Gi=gi2 values; a public module n formed by the product of f(?2) prime factors; an exponent v=2k(k>1), linked by the relationships of the type: Gi?Qiv?1. mod n or Gi?Qiv mod n. Among the m numbers obtained by increasing Qi or its inverse modulo n to modulo n square, k?1 times rank, at least one of them is different from ±gi. Among the 2m equations: x2?gi mod n, x2??gi mod n, at least one of them has solutions in x in the ring of modulo n integers.

Abstract: The invention concerns a method enabling a personal computer (1) to be authenticated by a server (2). The method comprises the step, which consists for the user in launching the execution of a log-on procedure software, by introducing personal identifiers (21) providing access to a signature private key (14) for long-term use relative to the duration of the session. The log-on procedure software produces: identification data of the session Id, a public ephemeral module n (9), a public exponent v and at least a pair of ephemeral pubic numbers G (11) and ephemeral private numbers Q (12) related by a generic equation of the type: G=Qv (mod n) or G×Qv=1 (mod n), an ephemeral certificate (13) linking, by means of said signature private key (14), Id (8) and n (9). The public ephemeral module n (9) is of reduced size relative to the signature private key (14).

Abstract: Process for the broadcasting of programmes with progressive conditional access and separation of the information flow, as well as the corresponding receiver,In order to form the elementary flow, groups of m successive elements of the multiplex are taken and for forming the complimentary flow groups of p successive elements of the multiplex are taken.Application to television with entitlement checking.

Abstract: A process for broadcasting conditional access programs which permits a progressive access. Scrambled program data is transmitted along with partial access checking messages and complete access checking messages such that subscribers having a partial access right may descramble portions of the scrambled data corresponding to information regarding only the identity of the conditional access programs, and subscribers having a complete access right may descramble the remainder of the scrambled data and view the conditional access programs. The conditional access programs may be television pictures, radio programs, or data broadcasts.

Abstract: According to the invention, the chip card issues a first certificate comprising its letter of credentials (Crc), an exponential (X), an optional message (M), these quantities being signed. The security module verifies the signature and in return issues a second certificate containing its letter of credentials (Crm), an exponential (Y), an optional message (M'), a cryptogram (C), these quantities being signed. A common secret key is constituted between the card and the security module by the exponentials and allows the card to interpret the cryptogram addressed to it and to act in accordance therewith.

Abstract: According to the invention, the control messages are constituted by a general addressing message (GCM), followed by shared addressing messages (SACM). The message (GCM) contains all the information common to all the user groups and a confirmation data item of the group of users and the messages (SACM) a shared address. Thus, the group is defined in a manner inherent in the control messages and can undergo reconfiguration at any time.Application to more particularly satellite broadcasting of television programmes.

Abstract: One chip microprocessor, which is more particularly designed to execute culation algorithms of a public code encoding system formed by a public function and a secret inverse function of the type comprising at least one programmable read-only memory, a processing unit and an input/output device, wherein it comprises a memory, in which is recorded at least one algorithm corresponding to the performance of said secret function, and wherein the programmable read-only memory contains the secret parameters constituting the secret code and recorded in an area of the read-only memory which is inaccesible from the outside, the processing unit including the multiplying circuits necessary for the execution of the algorithm.

Abstract: A receiver having an interface arrangement for connection between a television circuit and a conditional access sub-system conveys data via a bus having a four frame bus cycle period with a bit rate corresponding to the line rate. During a first part of the bus cycle period data is conveyed from the receiver to the sub-system sequentially as follows:i. an address block of 1 byte with the unique address of the sub-system with which the receiver is in communication,ii. a status block of 1 byte providing status information for the following blocks in the first part,iii,iv,v. three data blocks each of 93 bytes and each containing an entitlement message,vi. a keying block of 1 byte conveying keyboard or remote control commands, andvii,viii. a further block of either 1/2 byte (vii) or 21/2 bytes (vii+viii) conveying frame count information.