摘要:
A transponder (1) comprises at least one memory (MEM1, MEM2) for storing encrypted information (E_k(EPC, PI)) that has been encrypted by use of a key (k) and for storing the key (k) associated with the encrypted information (E_k(EPC, PI)). The transponder (1) is adapted to send the key (k) slower response than the encrypted information (E_k(EPC, PI)) in response to queries of a reading device (2), which is preferably done by delaying the transmission of the key (k) or by limiting the response rate at which the key (k) is transmitted. In particular the invention is related to RFID systems.
摘要:
The invention relates to an information carrier containing a non-clonable optical identifier (2) having an optical scattering medium (3) for being challenged by a light beam (5) and for scattering said light beam (5). In order to provide a secure information carrier (1), it is proposed that it further comprises a light absorbing means (3, 4) for reducing the intensity of said light beam (5) so that an integration time for obtaining a response signal by integrating the scattered light beam (8) is extended.
摘要:
An optical arrangement of at least a coherent light source (1), a strongly scattering object (5) (the PUF), and a pixe-lated photo-detector (6), wherein the pixels are comparable in size with the bright and dark patches of the speckle pattern produced by coherent radiation traversing the scattering object (5). Quantitively, the pixel size should be roughly λ/NA, where λ is the wave-length, and (i) NA=a/z for free-space geometry, with a being the beam radius and z being the distance between the exit surface of the PUF (5) and the pixelated detector (6), or (ii) NA is the numerical aperture of a lens (7) in an imaging geometry. In a preferred embodiment of the invention, there are tentative requirements that the pixels should be at least smaller than ηmaxλNA and preferably larger than ηmaxλ/NA, where (in an exemplary embodiment) ηmax=5 and ηmin=0.05, say. It will be understood by a person skilled in the art that the present invention is concerned with the optical arrangement of the PUF (5) and the photo-detector (6), rather than the photo -detector (6) per se.
摘要:
A cuvette (10) for storing a biological sample to be analyzed by means of a predefined detection technique is disclosed. The cuvette (10) is formed from a moldable material that contains particles (15a, 15b) at a concentration within a predefined range. The particles (15a, 15b) are randomly distributed, in order to form a unique pattern. Moreover, the particles (15a, 15b) have measurable physical properties, so that the unique pattern is detectable using the detection technique that is used to analyze the biological sample. The unique properties obtained by the randomly distributed particles (15a, 15b) render copying nearly impossible, since it is more complicated to distribute the particles in a predetermined pattern than to let them distribute randomly.
摘要:
The invention introduces, in the framework of secure multiparty computation based on homomorphic threshold cryptosystems, a protocol and a special type of multiplication gate that can be realized in a surprisingly simple and efficient way using just standard homomorphic threshold ElGamal encryption. As addition gates are essentially for free, the conditional gate not only allows for building a circuit for any function, but actually yields efficient circuits for a wide range of tasks.
摘要:
The semiconductor device (11) of the invention comprises a circuit and a protecting structure (50). It is provided with a first and a second security element (12A, 12B) and with an input and an output (14,15). The security elements (12A, 12B) have a first and a second impedance, respectively, which impedances differ. The device is further provided with measuring means, processing means and connection means. The processing means transform any first information received into a specific program of measurement. Herewith a challenge-response mechanism is implemented in the device (11).
摘要:
A method of and server (100) for enabling composition of a message at a remote terminal (101). The method comprises generating an image comprising a plurality of symbols representing input means, the symbols having an associated particular visual characteristic which is mutually different for at least two of the symbols, transmitting the image for display on the remote terminal (101), receiving a sequence of coordinates from the remote terminal (101), reconstructing the message as a sequence of input means represented by the symbols comprised in the image at the received coordinates, constructing an authentication code as a sequence of visual characteristics associated with the symbols comprised in the image at the received coordinates, and accepting the message as authentic if the authentication code matches a predetermined sequence of visual characteristics.
摘要:
A device (1) for decrypting encrypted images comprises an array of sensor elements (11) for sensing a first image, for example an encrypted image, and an array of display elements (12) for displaying a second image, for example a decrypted image. At least some display elements comprise integrated sensor elements, thus reducing the number of parts of the device. The integrated display/sensor elements (13) may be constituted by polymeric LED elements. The sensor function of the integrated elements may also be used for positioning the device relative to a terminal, and/or for checking a biometric feature of the user.
摘要:
A trusted display device (1) for, upon being superimposed on an untrusted display (2), reconstructing a graphical message, said device comprising a display screen (1a) having a plurality of independently addressable pixels. A plurality of sensors (1c) are associated with at least a subset of the pixels of said display screen (1a) and arranged such that they, when the displays (1, 2) are superimposed, are able to detect optically encoded information presented by an underlying pixel of the untrusted display (2) and adapt the activation of its pixels based on said information sensed.
摘要:
A method of generating a common secret between a first party and a second party, preferably devices (101-105) in a home network (100) that operate in accordance with a Digital Rights Management (DRM) framework. The devices calculate the common secret by evaluating the product of two polynomials P(x, y) and Q(x, z) using parameters previously distributed by a Trusted Third Party (TTP) and parameters obtained from the other party. Preferably the parties subsequently verify that the other party has generated the same secret using a zero-knowledge protocol or a commitment-based protocol. The method is particularly suitable for very low power devices such as Chip-In-Disc type devices.