Abstract: The invention relates to a method for operating a communication system including a primary station linked to a Core Network, said primary station serving a cell, a relay station served by the primary station and a secondary station served by the primary station, the method comprising the steps of the relay station establishing a connection with the primary station, including receiving in at least one first secure message from the primary station a first set of configuration parameters, the secondary station establishing a connection with the primary station, including receiving from the primary station in at least one second secure message a second set of configuration parameters linked to an upcoming data session, the relay station transmitting at least one transmitted service code from the first set, the secondary station establishing a direct communication with the relay station upon determination that the transmitted configuration parameters is included in the second set.

Abstract: Some embodiments are directed to a second cryptographic device (20) and a first cryptographic device (10). The first and second cryptographic devices may be configured to transfer a key seed. The key seed may be protected using a public key from one party and a private key from the other party. For example, a public key may be obtained from a private key through a noisy multiplication. At least one of the first and second cryptographic device may validate an obtained public key, e.g., to avoid leakage of the key seed or of a private key.

Abstract: Some embodiments are directed to a public-key encryption device (20) and a private-key decryption device (10). The public-key encryption device is configured to compute a second public-key matrix (u), the second public-key matrix (u) having fewer matrix elements than the first public-key matrix (b) of the private-key decryption device. This reduces computation and bandwidth requirements at the side of the public-key encryption device.

Abstract: The present invention relates to a method for a primary station distributing an encryption key to a plurality of secondary stations.

Abstract: Some embodiments are directed to a communication system comprising a one or more clients, a server and a middlebox. The middlebox may access to the multiple short-term server private keys of the server. The middlebox may recover a shared key that is negotiated between server and client by decapsulating encapsulation data using a stored client public key and a server private key from the key storage.

Abstract: An electronic key pre-distribution device (110) for configuring multiple network nodes (210, 211) with local key information is provided. The key pre-distribution device comprises applies at least a first hash function (147) and a second hash function (148) to a digital identifier of a network node. The first and second hash functions map the digital identifier to a first public point (141; H1(ID)) and a second public point (142; H2(ID)) on a first elliptic curve (131) and second elliptic curve (132). A first and second secret isogeny (135) is applied to the first and second public elliptic curve point (141, 142), to obtain a first private elliptic curve point (151) and second private elliptic curve point (152) being part of private key material (155) for the network node (210).

Abstract: A computer-implemented method of obfuscating a computer code comprises receiving (1201) an original computer program comprising a plurality of code blocks with computer instructions, the original computer program operable on input data within an input space, the original computer program operable to follow an execution path through the plurality of code blocks when receiving the input data, wherein the input space is segmented into at least one segment according to a segmentation, each segment comprising a subset of the input space containing inputs that correspond to a same execution path. A plurality of updated code blocks is included (1302) in the updated computer program. Selection code is operable 1303, during execution of the updated computer program, to select an updated code block of the plurality of updated code blocks in dependence on the input data. The selection code is included (1304) in the updated computer program.

Abstract: The present invention relates to a method for a secondary station to obtain a time reference in a cellular network in order to verify the freshness of received messages. The method comprises the steps of receiving a plurality of system information, SI, messages from a plurality of primary stations, said SI messages including each a respective time reference information related to the corresponding primary station, checking the validity of a received signature for each of the primary stations, checking a cell identifier for each of the primary stations with a valid signature, and ignoring time reference information from primary stations with a cell identifier being identical to another primary station and having an earlier value than the one from the other primary station, and deducing a local time reference from one or more of the time reference information originating from primary stations with a valid signature.

Abstract: An electronic key pre-distribution device for configuring multiple network nodes with local key information is provided. The key pre-distribution device applies at least a first hash function and a second hash function to a digital identifier of a network node. The first and second hash functions map the digital identifier to a first public point and a second public point on a first elliptic curve and second elliptic curve. A first and second secret isogeny are applied to the first and second public elliptic curve points, to obtain a first private elliptic curve point and second private elliptic curve point that are part of private key material for the network node.

Abstract: Some embodiments are directed to a cryptographic generation device for generating a random matrix. A random number initiation function may be executed in parallel for a number of random generating processes to obtain a random number state for each. Parallel random number generating processes together produce at least as many random numbers as elements in the random matrix.

Abstract: Some embodiments are directed to a second cryptographic device (20) and a first cryptographic device (10). The first and second cryptographic devices may be configured to transfer a key seed. The key seed may be protected using a public key from one party and a private key from the other party. For example, a public key may be obtained from a private key through a noisy multiplication. At least one of the first and second cryptographic device may validate an obtained public key, e.g., to avoid leakage of the key seed or of a private key.

Abstract: Some embodiments relate to a first electronic network node is provided (110) configured for a cryptographic operation. The first network node is configured to receive as input a difficulty parameter (d), and a structure parameter (n), and to obtain a shared matrix (A), the shared matrix being shared a second network node through a communication interface, entries in the shared matrix (A) being selected modulo a first modulus (q), the shared matrix (A) being a square matrix (k×k) of dimension (k) equal to the difficulty parameter (d) divided by the structure parameter (n), the entries in the shared matrix (A) being polynomials modulo a reduction polynomial (ƒ) of degree equal to the structure parameter (n), said cryptographic operation using the shared matrix.

Abstract: Some embodiments are directed to a cryptographic device (20). A reliable bit function may be applied to a raw shared key (k*) to obtain reliable indices, indicating coefficients of a raw shared key, and reliable bits derived from the indicated coefficients. Reconciliation data (h) may be generated for the indicated coefficients of the raw shared key. A code word may be encapsulated using the reliable bits by applying an encapsulation function, obtaining encapsulated data (c) which may be transferred.

Abstract: Some embodiments are directed to a compiling device (100) configured for selecting of protective transformations to improve security of a computer program. The compiling device is configured to assign protective transformations to parts of the data flow graph, and obtain a compilation of the computer program representation from at least the data flow graph and the assigned protective transformations which satisfy the security and/or the performance target.

Abstract: A first device and a second device are disclosed for reaching agreement on a secret value. Herein, the second device comprises a receiver configured to receive information indicative of a reconciliation data h from the first device, a processor configured to compute a common secret s based on an integer value b, an equation, and system parameters. The processor is configured to compute b based on a key exchange protocol. The first device has a number a in approximate agreement with the number b. The first device comprises a processor configured to determine a common secret s based on an integer value a an equation, and system parameters, and determine a reconciliation data h. The first device further comprises a transmitter configured to transmit information indicative of the reconciliation data h to the second device.

Abstract: Some embodiments are directed to a compiler device (400) arranged for obfuscation of a computer program. The compiler device performs a live variable analysis on the computer program representation, and modifies the computer program representation to encode a first variable using at least a second variable as an encoding parameter.

Abstract: Some embodiments are directed to a system with a first cryptographic device (10) and second cryptographic device (20). The devices may compute a final seed from a preshared secret known to the devices, and on a pre-seed that exchanged between them. The final seed may be used to derive a common object (a).

Abstract: Some embodiments are directed to a public-key encryption device (20) and a private-key decryption device (10). The public-key encryption device is configured to compute a second public-key matrix (u), the second public-key matrix (u) having fewer matrix elements than the first public-key matrix (b) of the private-key decryption device. This reduces computation and bandwidth requirements at the side of the public-key encryption device.

Abstract: A computer-implemented method of obfuscating a computer code comprises receiving (1201) an original computer program comprising a plurality of code blocks with computer instructions, the original computer program operable on input data within an input space, the original computer program operable to follow an execution path through the plurality of code blocks when receiving the input data, wherein the input space is segmented into at least one segment according to a segmentation, each segment comprising a subset of the input space containing inputs that correspond to a same execution path. A plurality of updated code blocks is included (1302) in the updated computer program. Selection code is operable 1303, during execution of the updated computer program, to select an updated code block of the plurality of updated code blocks in dependence on the input data. The selection code is included (1304) in the updated computer program.

Abstract: Some embodiments relate to an electronic network node (110) configured for a cryptographic operation. The network node obtains a shared matrix (A) by selecting integers, polynomials, and/or polynomial-coefficients from a shared pool, the shared pool being shared with the second network node, wherein the selecting is done according to one or more selection functions.