Proton World International N.v.

Stmicroelectronics (rousset) Sas

Frank Cuypers

Olivier Van Nieuwenhuyze

Pierre-Yvan Liardet

Joan Daemen

Gilles Van Assche

Patrick Dumoulin

The invention relates to a method of authentication of a contactless communication circuit, PICC, by a contactless communication terminal, PCD. Within the PCC, a first number is generated and without encryption, transmitted to the PCD. Within the PCD a second number is determined by decryption of the first number with a first key. The determination of a third number is based on the second number, and the determination of a fourth number is by encryption of the third number with the first key. Decryption of the fourth number with the first key to obtain the third number and an interruption of the authentication if a sixth number obtained from the third number is different from a seventh number, is performed by the PICC.

Authentication of a card by contactless reading

A contactless communication circuit (card) communicates with a proximity coupling device (reader). The card hosts at least two applications. The card initializes an identifier of a communication protocol to a first value. In response to a failure of a transaction with the reader, the card increments a counter. When the counter reaches a threshold, the card changes the identifier to a second value.

Application selection in a mobile terminal

The invention relates to a method of authentication of a contactless communication circuit, PICC, by a contactless communication terminal, PCD. Within the PICC, a first number is generated by encryption of a second random number, and the first number is sent to the PCD. Within the PCD, a third number is generated by decryption of the first number. Also within the PCD, a fourth number is determined and encrypted to generate a fifth number. The fifth number has first and second portions. Back within the PICC, a sixth number is determined, which is used in the determination of a seventh number. The seventh number is determined by encryption by a cipher block chaining operating mode of the sixth number with an initialization vector equal to the first portion. If the seventh number is different from the second portion, the authentication is interrupted.

A method for protecting the generation, by an electronic circuit, of at least one prime number by testing the primality of successive candidate numbers, including for each candidate number tests of primality with respect to prime numbers of at least one set of consecutive prime numbers, wherein the order of application of the tests is modified at least from one prime number generation to another.

Protection of a prime number generation against side-channel attacks

A method for protecting a generation, by an electronic circuit, of at least one prime number by testing the prime character of successive candidate numbers, including: for each candidate number: the calculation of a reference number involving at least one first random number, and at least one primality test based on modular exponentiation calculations; and for a candidate number having successfully passed the primality test: a test of consistency between the candidate number and its reference number.

Growing community of inventors

De Pinte, Belgium

Frank Cuypers