Ecole Polytechnique Federale De Lausanne

Nagravision S.a.

Nokia Corporation

Global Id Sa

Serge Vaudenay

Pascal Junod

Imad Aad

Betül Durak

Pentti Valtteri Niemi

Rafik Chaabouni

Lambert Sonna Momo

Atefeh Mashatan

Jean Monnerat

Fatih Balli

Ioana C Carlson

A method for recognizing and/or identifying a user () with a chip (C) in an electronic identity object storing a digital identity (), the method comprising steps of: —establishing a wireless or electrical connection between the electronic identity object (C) and a verification terminal (T); —verifying, in the electronic identity object, if the verification terminal is authorized to communicate with the electronic identity object (C), and in response of a positive verification sharing a secret (K): using the shared secret (K) for establishing an encrypted symmetric data link () between the electronic identity object and the verification terminal (T); transmitting, through the encrypted data link (), said digital identity () stored in the electronic identity object to the verification terminal (T); and verifying in the verification terminal (T) the authenticity of said digital identity ().

Method, electronic identity object, and terminal for recognizing and/or identifying a user

The invention is related to a method allowing a prover holding a secret key (x) to prove its identity to a verifier and to prove to this verifier that he is within a predetermined distance of this verifier, said method comprising an initialization phase during which:

Method and device for proving his identity

A method for providing efficient management of certificate revocation may comprise storing a list of identifiers of digital certificates including a revocation list defining a list of revoked certificates in an accumulator, storing a witness value in association with at least some entries in the revocation list in which the witness value provides proof of the membership or non-membership of an identifier in the revocation list, enabling generation of a new accumulator and a new witness value responsive to each insertion or deletion of an entry in the revocation list, and enabling batch updates to the revocation list using a reduced bitlength value generated based on to a ratio of a value generated based on elements added to the revocation list to a value generated based on elements deleted from the revocation list. A corresponding apparatus is also provided. A method for certificate authorities (CA) that use Bloom filters for certificate revocation list (CRL) compression that enables the CA to hash only the entry that is to be un-revoked so that a good compression rate may be provided while avoiding computation of the entire CRL for each un-revocation.

Method and apparatus for providing efficient management of certificate revocation

Provided is a method to generate sub-keys based on a main key in a case in which, each sub-key gives no information to recover the main key. The method has the steps of obtaining a first value by applying to the main key a linear diversification by mixing the main key with a constant and applying to the first value a non-linear transformation. The non-linear transformation includes obtaining a second value by applying the first value to a substitution layer, obtaining a third value formed of N blocks of the same size by using a diffusion box of multi-permutation type based on the second value, obtaining the fourth value formed by blocks, obtaining the fifth value by applying to the fourth value a substitution layer, obtaining the sub-key by applying to the fifth value a symmetrical encryption module. The first value serves as the key input for this method.

Method for generating pseudo-random keys

The purpose of this invention is to propose a new encryption method which offers a high level of security combined with a high execution speed. This aim is achieved by a method to encrypt or decrypt blocks of data X to Y, based on a main key R, this method using several serially connected modules, each module using a sub-key RA derived from the main key R.

Device and method for encrypting and decrypting a block of data

The aim of the invention is to propose the generation, verification and denial of an undeniable signature which has a size smaller than the currently available undeniable signatures, i.e. less than 80 bits. This aim is achieved by the method to generate an undeniable signature (y, . . . , y) on a set of data, this method comprising the following steps: (1) transforming the set of data (m) to a sequence of a predetermined number (t) of blocks (x, . . . , x), these blocks being members of an Abelian group, this transformation being a one way function, and (2) applying to each block (x) a group homomorphism (f) to obtain a resulting value(y), in which the number of elements of the initial group (G) is larger than the number of elements (d) of the destination group (H).

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Crissier, Switzerland

Serge Vaudenay