Abstract: In a method for generating program code in a load format for a portable data carrier, a pseudo library is used, which differs from the library located on the data carrier in such a way that at least some of the internal workings of the library located on the data carrier are absent or hidden or masked in the pseudo library. In a method for providing executable program code in the portable data carrier, the program code in load format is linked relative to the library located on the data carrier. A device and a computer program product have corresponding features. The invention provides secure, privacy-safeguarding technology, which allows the generation of program code in a load format for a portable data carrier and the provision of executable program code in the portable data carrier.

Abstract: The invention relates to a method for testing the authenticity of a data carrier (1) and/or an external device (2) which enters into data exchange with the data carrier (1). According to the invention, the data carrier (1) and the external device (2) are each equipped with a special additional apparatus (4, 6) for generating and/or testing authenticity data. Data transmission between the data carrier (1) and the external device (2) as required for authenticity testing is performed at least partly via a special transmission channel (B). The transmission channel (B) for transmitting authenticity data is separated physically or logically from a transmission channel (A) for transmitting standard data so that there is no mutual interference of data transmission via the two transmission channels (A, B).

Abstract: The invention relates to a method for operating a chip card (C), a microprocessor for being inserted into the chip card (C) and a computer program product, as well as a method for manufacturing and/or for maintaining a chip card (C) which is operated with the help of a method described above. Here central multi-tasking kernel (MTK) is provided, which controls the entire operation of the chip card (C), so that there can be activated a plurality of application programs (A) on the chip card (C) at the same time, an application program (A) also being able to realize security technical functions for the chip card (C).

Abstract: In a method for generating program code in a load format for a portable data carrier, a pseudo library is used, which differs from the library located on the data carrier in such a way that at least some of the internal workings of the library located on the data carrier are absent or hidden or masked in the pseudo library. In a method for providing executable program code in the portable data carrier, the program code in load format is linked relative to the library located on the data carrier. A device and a computer program product have corresponding features. The invention provides secure, privacy-safeguarding technology, which allows the generation of program code in a load format for a portable data carrier and the provision of executable program code in the portable data carrier.

Abstract: A method for testing the authenticity of a data carrier having at least an integrated circuit with memory units and logic units as well as a data line for data exchange with an external device. The invention is characterized in that the integrated circuit additionally has a separate hard-wired circuit for transmitting and/or receiving data during the power-up sequence, which is used for authenticity testing, the first transmission or reception of data being completed within a defined time domain of the power-up sequence in which the data line has no defined state.

Abstract: A method for testing the authenticity of data carriers having integrated circuits, memory and logic means to determine physical properties of each circuit that are distinctive of this circuit and use them to obtain data characteristic of each circuit. According to the present invention, one preferably evaluates the different programming times of the memory cells of an E.sup.2 PROM memory, an evaluation which can be determined by various methods and processed as distinctive characteristics. Other individual properties that can be utilized are, for example, distinctive features of a memory input.

Abstract: The present invention relates to a data carrier arrangement having an integrated circuit (1) for obtaining of services, goods or the like, the integrated circuit (1) having at least one non-volatile data memory (2) with a predetermined number of memory cells which are readable, erasable and writable. In the data carrier arrangement described, the integrated circuit (1) has along with the data memory (2) a counter (3) consisting of a plurality of stages, and a control and security logic (4), the counter (3) being operable only in one predetermined direction, the size of the data memory (2) being selected such that its memory cells are adapted to the steps of the counter, and the control and security logic (4) controlling, among other things, the data transfer between the memory (2) and the counter (3) in such a way that before each use of the data carrier the current memory value is transferred to the counter and after use of the data carrier the memory content is updated with the new counter reading.