Abstract: In a method for forming a CRC value using a plurality of data blocks, the CRC protection can be improved even further by virtue of the fact that, in order to form the CRC value, data blocks which are not transmitted to a receiver or have not been transmitted to a receiver are placed in front of data blocks which are transmitted to the receiver or have been transmitted to the receiver.

Abstract: 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: a) generating at least one sequence of a number K of zero bits, using K?{1, . . . , N}, by means of a first transformation of the respective input bit string to at least one predetermined position in the respective input bit string for generating at least one first intermediate bit string; b) linking the at least two first intermediate bit strings by means of the integer multiplication of the processor unit for generating at least one second intermediate bit string; and c) transforming the at least one second intermediate bit string by means of a second transformation for generating a result bit string.

Abstract: 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.

Abstract: There is described a method for transmitting synchronization messages, for example PTP messages of the IEEE 1588 standard, the PTP message being inserted into a data packet in line with the Internet Protocol, the data packet having an IP header, and the data packet having a UDP header. In this case, for the encrypted transmission on the PTP message, the data packet is addressed to a UDP port that is reserved for encrypted PTP messages, the data packet is provided with an additional S-PTP header that is provided for encryption, the PTP message is extended with a pseudo random number, and the PTP message is encrypted together with the pseudo random number.

Abstract: The embodiments provides a method for processing data. According to the invention, an elliptic curve with an order m which corresponds to a product of a first cofactor c and a prime number q is provided, wherein the order (q?1) of the multiplicative group of the prime number q corresponds to a product of a second cofactor I and at least two prime divisors s1, . . . , sk, wherein the at least two prime divisors s1, . . . , sk are each greater than a predetermined bound of 2n; and a chosen method is applied to provided data using the provided elliptic curve for providing cryptographically transformed data. The invention enables cryptographically transformed data to be provided while simultaneously minimizing the probability of a successful attack.

Abstract: 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: a) generating at least one sequence of a number K of zero bits, using K?{l, . . . , N}, by means of a first transformation of the respective input bit string to at least one predetermined position in the respective input bit string for generating at least one first intermediate bit string; b) linking the at least two first intermediate bit strings by means of the integer multiplication of the processor unit for generating at least one second intermediate bit string; and c) transforming the at least one second intermediate bit string by means of a second transformation for generating a result bit string.

Abstract: The embodiments provides a method for processing data. According to the invention, an elliptic curve with an order m which corresponds to a product of a first cofactor c and a prime number q is provided, wherein the order (q?1) of the multiplicative group of the prime number q corresponds to a product of a second cofactor I and at least two prime divisors s1, . . . , sk, wherein the at least two prime divisors s1, . . . , sk are each greater than a predetermined bound of 2n; and a chosen method is applied to provided data using the provided elliptic curve for providing cryptographically transformed data. The invention enables cryptographically transformed data to be provided while simultaneously minimizing the probability of a successful attack.

Abstract: 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.

Abstract: There is described a method for transmitting synchronization messages, for example PTP messages of the IEEE 1588 standard, the PTP message being inserted into a data packet in line with the Internet Protocol, the data packet having an IP header, and the data packet having a UDP header. In this case, for the encrypted transmission on the PTP message, the data packet is addressed to a UDP port that is reserved for encrypted PTP messages, the data packet is provided with an additional S-PTP header that is provided for encryption, the PTP message is extended with a pseudo random number, and the PTP message is encrypted together with the pseudo random number.

Abstract: In the case of cryptographic processing with the aid of an elliptic curve, parameters of the elliptic curve are stored in a memory of a computer. These parameters are each of substantial length. The elliptic curve is transformed in order to shorten at least one parameter significantly in length and to ensure that the high security level is unchanged in the process. One parameter is preferably shortened to 1, ?1, 2 or ?2 with the aid of an algorithm, whereas the other parameters have a length of several 100 bits. The shortening of even one parameter is clearly reflected in the case of devices which have little memory space.