Abstract:
A method for decrypting the encrypted messages sent by a transmission device to a first electronic device (SIM) associated with a first trusted authority (TA-SIM) and to a second electronic device (ME). The method comprises the steps of:
a) associating a single joint identity with the first (SIM) and the second (ME) devices which is identificative of a common entity comprising the first (SIM) and the second (ME) devices; b) carrying out a single encryption operation of a message by the transmission device, by using the joint identity and transmitting the encrypted message to both devices; c) generating first (W SIM ) and second (W ME ) decryption tokens by the first (SIM) and the second (ME) devices, respectively; d) providing said first token to the second device and said second token to the first device; e) generating, by starting from said tokens, by the first and second devices, of a joint decryption key (W) in order to decrypt the encrypted message.
Abstract:
L'invention concerne un procédé de chiffrement ou de déchiffrement d'un flux de données binaires, comprenant des étapes de génération d'un flux binaire de chiffrement (BS) et de combinaison par une opération logique réversible de chaque bit du flux de données binaires à un bit du flux binaire de chiffrement, la génération du flux binaire de chiffrement comprend des étapes consistant à : générer un bloc d'entrée (CB1, CB2, CB3) en appliquant une fonction cryptographique (ENC1, ENC2, ENC3) utilisant une clé secrète (SK) à un bloc (RN, CB1, CB2), et générer le flux binaire de chiffrement à partir du bloc d'entrée en combinant entre eux les bits du bloc d'entrée par des opérations logiques, de manière à éviter que le bloc d'entrée puisse être déterminé à partir du flux binaire de chiffrement uniquement.
Abstract:
A method for establishing a communication between a first electronic device (SIM) associated with a first Trusted Authority (TA-SIM) and a second electronic device (ME). The method comprises the steps of:
making a first key (Ksyk SIM ) available to the first device for the communication between the first Authority and the first device; providing a second Trusted Authority (TA-ME), associated with the second device and distinct and autonomous with respect to said first Authority; such second Authority may generate a second key (Ksyk ME ) in order to communicate with the second device.
Furthermore, the method comprises the steps of:
making the second key available to the second device; providing the first and second device with a communication key (Ks) to be used in said communication, through at least one of said first and second Authorities.
Abstract:
Method of establishing an encrypted communication by means of keys between a first electronic device (SIM) associated to a first trusted authority (TA-SIM) and a second electronic device (ME). The method comprises the steps of:
generating a first secret key (Ks) associated to the first device for the management of said communication; generating, at least in part by means of said first authority, a second secret key (Ks) associated to the second device for the management of said communication.
The method is characterised in that the step of generation of the first key is performed at least in part by means of a second trusted authority (TA-ME) associated to the second device that is distinct and autonomous from said first authority. Or, the generation of the first key is performed, at least in part, by the second device passing through the second trusted authority.