Gemalto Sa

Gemplus

Pascal Moitrel

Philippe Proust

Eric Brier

Olivier Benoit

Pascal Guterman

Laurent Sustek

Jacques Fournier

Mireille Pauliac

Johan Pascal

Cedric Cardonnel

A method of protecting a telecommunication terminal having a chip-card-type personal component which is required for telecommunication network access. The terminal includes a processing unit, at least one operating memory element containing the information necessary to the operation of the terminal, i.e. a terminal operating program, and the data necessary to the program. The method involves: a) encrypting the contents of the operating memory element of the telecommunication terminal using a pre-determined key K which is necessary for decryption; and b) allowing the terminal to commence decryption once the terminal has been started with a start-up program that is saved in a secure memory element and once the key for decryption has been calculated by same.

Method of protecting a mobile-telephone-type telecommunication terminal

The invention relates to a method for secure data transmission in connections between two functional modules of an electronic unit. A first module of a message of k bits in a word code of n bits is injection coded with a constant Hamming weight of w. The word of code is transmitted to a second module. An error signal is generated when the Hamming weight of the word of code of n bits, received by the second module, is different from w. In the absence of error, the code word is decoded, where k, w and n are whole numbers. The invention further relates to a corresponding electronic circuit.

Secure data transmission between two modules

Access control to data processing means, such as a smart card, is made secure by simulating a comparison block by block of part of a secret code with part of a presented code through a block-by-block comparison of part of the presented code and part of a determined number when the presented code is found to be erroneous. Each time the card is used, a constant number of operations are applied to the presented code and at least for part of the secret code, and at most for a complementary part to the determined number, thus avoiding different signatures of power consumption for different presented codes.

Secret code security access to data processing means

Growing community of inventors

Aubagne, France

Pascal Moitrel