| Patent application number | Description | Published |
| 20080201398 | Determination of a Modular Inverse - In side-channel attack-resistant encoding methods, a return value (r) is determined as the modular inverse of an input value (a), by a module (M). A resistance to side-channel attack can be achieved with minimal restrictions on implementation on determination of the modular inverse with minimal technical complexity. To this end, in a first sub-step, a first product (d) of the input value (a) and a random number is generated (c), in a second sub-step, the modular inverse (e) of the first product (d) is determined by the module (M), in a third sub-step, a second product (b) of the random number (c) is determined by the modular inverse (e) and in a fourth sub-step the return value (r) is set to the same as the second product (b). | 08-21-2008 |
| 20090024352 | Method, Device and System For Verifying Points Determined on an Elliptic Curve - Conventional cryptographic methods that are based on elliptic curves are prone to side-channel attacks. Previously known methods for preventing side-channel attacks have the disadvantage of requiring high arithmetic capacity and a large amount of available memory space. The proposed method overcomes said disadvantage by using a process for verifying points on elliptic curves which saves arithmetic capacity and memory space. | 01-22-2009 |
| 20090136025 | Method for scalarly multiplying points on an elliptic curve - A method performs scalar multiplication of points on an elliptic curve by a finite expandable field K of a first field F | 05-28-2009 |
| 20090235073 | Authentication method and communications system used for authentication - An authentication method authenticates between subscribers of a communications system using an asymmetric elliptic curve encryption algorithm. The method involves providing a first and at least one second subscriber having a first or second secret key known only to the respective subscriber and a public key; authenticating an inquiry transmitted by the first subscriber with respect to the validity of the first certificate contained therein and associated with the first subscriber; calculating the response of the second subscriber associated with the inquiry; randomized encryption of the calculated response and a second certificate associated with the second subscriber using the public key; decryption and authentication of the response transmitted by the second subscriber with respect to the validity of the second certificate contained therein. | 09-17-2009 |
| 20090285388 | Cryptographic Method with Elliptical Curves - A method determines an elliptical curve, suitable for a cryptographic method. An elliptical curve to be tested is prepared. The order of a twisted elliptical curve associated with the elliptical curve to be tested is determined. It is automatically checked whether the order of the twisted elliptical curve is a strong prime number. If the order of the twisted elliptical curve is a strong prime number, the elliptical curve to be tested is selected as an elliptical curve suitable for cryptographical methods. | 11-19-2009 |
| 20090292921 | METHOD FOR THE ENCRYPTED DATA EXCHANGE AND COMMUNICATION SYSTEM - The embodiments relate to a method for the encrypted data exchange between subscribers of a communication system using cryptography based on elliptical curves, wherein upon a query by a first subscriber a scalar multiplication is calculated by the second subscriber, wherein merely part of the result of the scalar multiplication is returned to the first subscriber as a response. The invention relates to a communication system. | 11-26-2009 |
| 20100146624 | Method and apparatus for protection of a program against monitoring flow manipulation and against incorrect program running - Protection program commands are inserted into at least one program command sequence of program commands in a program, to produce and check a monitoring flow marking sequence. | 06-10-2010 |
| 20100172490 | METHOD FOR THE SECURE DETERMINATION OF DATA - The aim of the embodiments is to provide a method for the secure processing of data, in which security is increased in relation to side channel attacks. To achieve this, operation codes for commanding co-processors are determined, for example for the bit-dependent transposition of register contents. The solution exploits the fact that as a result of the technical configuration for the co-processor, a shift of register contents, for example from register A to register B cannot be differentiated from the exterior from a shift from register A to register C. | 07-08-2010 |
| 20100194609 | Method and Device For Coding Data Words - The invention relates to a method for coding a data word having a prescribed quantity of arbitrary data symbols and a prescribed quantity of a reference data symbols, wherein a checksum with a prescribed quantity of cheek symbols is calculated for the data word and the quantity of arbitrary data symbols corresponds at least to the quantity of check symbols of the checksum. | 08-05-2010 |
| 20100322423 | Data Transmission Method, and Tachograph System - In a data transmission method for a tachograph system, digital messages are transmitted between a speed transmitter (MS) and a recording unit (RU). The digital messages contain a pair of keys including a public key (KMP, KRP) and a private key (KMS, KRS), as well as a certificate (ZM, ZR) derived from the respective pair of keys. The public keys (KMP, KRP) and the certificates (ZM, ZR) are mutually verified between the recording unit (RU) and the speed transmitter (MS). If the verification is positive, the speed transmitter (MS) detects sensor data, and a digital message is generated therefrom. In addition, the speed transmitter (MS) generates authentication data for the message in accordance with the pair of keys (KMP, KMS) thereof. The message and the authentication data are transmitted to the recording unit and are processed there in accordance with a validity of the authentication data verified by the recording unit (RU). | 12-23-2010 |
| 20110035588 | Encoding Method and Device for Securing a Counter Meter Reading Against Subsequential Manipulations, an Inspection Method and Device for Verifying the Authenticity a Counter Meter Reading - The invention relates to an encoding method for identifying a subsequential manipulation of a counter meter reading consisting, when the counter reading is increased or decreased, in activating the computation of a new encoded meter reading and in calculating a new encoded meter reading by applying a forward chain one-way function to the encoded meter reading, wherein a complex variable domain of said forward chain one-way function is included into the antecedent domain thereof. The invention also relates to a method for verifying the authenticity of a counter meter reading consisting in subtracting test meter readings based on the meter reading for obtaining the number of tests, in producing an encoded test meter reading by applying the chain one-way function to the encoded meter reading, in applying the chain one-way function with the number of tests and in comparing the test meter reading with the final encoded meter reading and, if the test meter reading defers from the final encoded meter reading, a negative status signal is emitted. An encoding system for carrying out said encoding method and a verification system for carrying out the verification method are also disclosed. | 02-10-2011 |
| 20110107097 | METHOD FOR ENCODED DATA EXCHANGE AND COMMUNICATION SYSTEM - In a system and method for encrypted data exchange between entities (users) of a communication system using cryptography based on elliptic curves, in response to a challenge of a first user a scalar multiplication is calculated by the second user, wherein only part of the result of the scalar multiplication is sent back as response to the first user. | 05-05-2011 |
| 20110131395 | METHOD AND PROCESSOR UNIT FOR IMPLEMENTING A CHARACTERISTIC-2-MULTIPLICATION - The method for implementing a characteristic-2-multiplication of at least two input bit strings each having a number N of bits by means of a processor unit suitable for carrying out an integer multiplication, having the following steps:
| 06-02-2011 |
| 20110163818 | APPARATUS AND METHOD FOR GENERATING A RANDOM BIT SEQUENCE - An apparatus for generating a random bit sequence has a ring oscillator which includes inverting digital devices and on which an oscillator signal can be tapped. An intermediate storage element monitors and stores fluctuating levels of the oscillator signal. At least two controllable switch devices for simultaneously exciting at least two harmonic wave edges of the ring oscillator are provided in a signal path of the ring oscillator. The phasing of the two harmonic wave edges and a potential convergence thereof are subject to statistical fluctuations, which are used as a basis for the random bit generation. A corresponding random number generator can be used in particular as an FPGA for security applications, such as cryptographic methods. The apparatus has substantially digital components, which are easy to produce in a standardized manner. A dedicated regulating circuit is not necessary. The apparatus is also robust toward exterior influences. | 07-07-2011 |