Abstract: A system, comprising an authentication module to generate a challenge to authenticate a user, the challenge to be distributed to members of a set of verifying parties; and grant the user access to a resource upon receiving an authenticating response to the challenge; and a combiner module to receive partial responses from members of the set of verifying parties upon verification of the user by each member, the verification made using a provided contextual identifier of the user; based on the partial responses reaching a threshold number of responses, combine the partial responses to obtain a combined response, and provide the combined response to the authentication module as an authenticating response to the challenge.

Abstract: In an example, apparatus is described. The apparatus comprises a processor associated with a secure interface of the apparatus for managing communications with a communications interface communicatively coupled to the secure interface via a communication path. The apparatus further comprises a non-transitory machine-readable medium storing instructions readable and executable by the processor. The instructions cause the processor to receive, via the secure interface, a request generated by a requesting entity for the apparatus to provide information about a computing system associated with the apparatus. The instructions further cause the processor to, in response to the request, produce a message comprising the information, where the message comprises an indication that the apparatus produced the message.

Abstract: Examples provide machine readable storage storing instructions arranged, when processed, to facilitate authentication using an authenticator, the instructions comprising instructions to generate, by an initial authenticator, authentication data associated with a further authenticator; the authentication data comprising private data and a public credential; the public credential and private data being for use in producing authentication information to authenticate the further authenticator to a relying party; and send data derived from the authentication data to network storage commonly accessible by the initial authenticator and the further authenticator.

Abstract: Examples relate to machine readable storage storing instructions arranged, when processed, to implement authentication using an authenticator, the instructions comprising instructions to: generate, by an initial authenticator, a public key associated with a further authenticator using a secret associated with the initial authenticator and the further authenticator; and output the public key associated with the further authenticator for sending to a relying party.

Abstract: An apparatus, machine-readable instructions and a system to provision partial signing keys to approver devices are provided. A first plurality of partial signing keys is provisioned to a set of first approver devices. A request to execute a command is received and forwarded to multiple ones of the first approver devices. Responsive to the forwarded request, a threshold number of distinct partial signatures are received indicating approval for execution of the command, the approval being verifiable by combining of the threshold number of different partial signatures to generate a complete signature. The apparatus provisions a further partial signing key to a further approver device subsequent to execution of the approved command.

Abstract: In an example, a computing device is described. The computing device comprises a memory to store a set of states and a corresponding set of non-overlapping time intervals. The computing device further comprises a timing unit to indicate a time at which a signature is to be produced. The computing device further comprises a processor to: identify which time interval of the set of non-overlapping time intervals includes the indicated time; generate a signing key based on a state associated with the identified time interval; and produce a signature, under a stateful signature scheme, with the signing key.

Abstract: In an example, a computing device is described. The computing device comprises a processor. The processor is to generate a key using a value as an input to generate the key. The processor is further to, in response to generating the key, exclude the value from future use as the input. The processor is further to store an indication of a subsequent value to use as the input to generate a subsequent key. The indication is cryptographically associated with an entity to control third-party access to the indication.

Abstract: In an example, a computing device is described. The computing device comprises an interface to receive a request from a signer for a state. The state is to be used as an input to generate a key under a stateful signature scheme. The computing device further comprises a processor. The processor is to identify an available state that the signer is authorized to use in response to the request received via the interface. The available state is identified from a set of states that can be used by the signer to maintain statefulness of the stateful signature scheme. The processor is further to instruct a reply to be sent to the signer via the interface. The reply comprises an indication of the state that the signer is authorized to use.

Abstract: In an example, a computing device is described. The computing device comprises a communication interface and a processor. The processor is to determine whether a signature, produced by a signer, is derived from a free state under a stateful signature scheme. The free state is a state that has not been used as an input to generate a signing key. The signature is encrypted by the signer. The processor is further to, in response to determining that the signature is derived from a free state, decrypt the encrypted signature. The processor is further to transmit the decrypted signature to a recipient via the communication interface.

Abstract: Example implementations provide a computer program product for authenticating a number of grouped product-packaging pairs, in which each product-packaging pair comprises a respective message, associated with a respective product, and a respective signature associated with the message; the computer program product comprising machine executable instructions arranged, when processed, to: read the product messages and the signatures from the grouped product-packaging pairs; determine and store bilinear computation results associated with each of the messages, and each of the signatures; and determine, from the stored bilinear computation results, whether or processed not at least one product-packaging pair of the number of grouped product-packaging pairs is authentic.

Abstract: In Example implementations provide a computer program product to authenticate a set of components associated with a device; the components having associated respective shares (s1..sn) of a private key of a private-key/public key pair (sk,pk); the computer program product comprising: instructions to create a signature from the shares (s1..sn) and a message, m, associated with the components; and instructions to generate authentication data comprising at least the signature for transmitting to an authentication server.

Abstract: According to aspect of the present disclosure there are provided methods and apparatus for printing to a group of printers in a network, including a method comprising provisioning each printing device of the plurality of printing devices with a respective private cryptographic key, defining a first group of printing devices comprising a first subset of the plurality of printing devices, generating a first group public key for the defined first group of printing devices, the first group public key generated based on public cryptographic keys corresponding to the respective private cryptographic keys provisioned to the first subset of the plurality of printing devices, and providing the first group public key to a user.

Abstract: Example implementations provide machine readable storage storing machine executable instructions, arranged, when processed by a processor, for a succeeding generation player device accessing an unassigned share in a secret the instructions comprising C instructions to: (a.) receive an intermediate generation share of a set of intermediate shares, the intermediate generation share being arranged to facilitate access to the unassigned share and the intermediate generation share having been derived by an intermediate generation player device from shares of further shares provided by a set of preceding generation player devices; (b.) receive, from a set of other intermediate generation player devices, a set of other intermediate generation shares of the set of intermediate shares, to facilitate access by the succeeding generation player device to the unassigned share in conjunction with the intermediate generation share; and (c.

Abstract: A system, comprising an authentication module to generate a challenge to authenticate a user, the challenge to be distributed to members of a set of verifying parties; and grant the user access to a resource upon receiving an authenticating response to the challenge; and a combiner module to receive partial responses from members of the set of verifying parties upon verification of the user by each member, the verification made using a provided contextual identifier of the user; based on the partial responses reaching a threshold number of responses, combine the partial responses to obtain a combined response, and provide the combined response to the authentication module as an authenticating response to the challenge.

Abstract: Examples relate to machine readable storage storing instructions arranged, when processed, to realise methods of verifying as valid a received signature, associated with a respective received message, generated using a Merkle Signature Scheme comprising a Merkle Tree, the Merkel Tree comprising a root node, a number of leaf nodes and a number of intermediate nodes disposed between the root node and the leaf nodes; the instructions comprising instructions to: calculate a hash value in response to receiving the respective message; determine that the calculated hash value corresponds to a stored previously verified hash value calculated in response to a previously received message, and verify the received signature as valid based on the stored previously verified hash value.

Abstract: In an example, an apparatus is described. The apparatus comprises a memory device comprising a set of logical cells. A logical cell of the set of logical cells indicates a data value by an amount of charge stored in a physical cell of the logical cell. Charge leakage between the physical cell and an adjacent physical cell of the logical cell is to occur at a rate that at least partially depends on a relative amount of charge stored in the physical cell and the adjacent physical cell. A set of data values indicated by the set of logical cells is to change over time due to the charge leakage. The set of data values indicated by the set of logical cells is representative of information that is valid over an estimated period of time, which is based on the rate of charge leakage.

Abstract: In an example, an apparatus is described. The apparatus comprises a processor to interface with a computing system and a memory device comprising a set of logical cells. A logical cell of the set of logical cells indicates a data value by an amount of charge stored in a physical cell of the logical cell. Charge leakage between the physical cell and an adjacent physical cell of the logical cell is to occur at a rate that at least partially depends on a relative amount of charge stored in the physical cell and the adjacent physical cell. The apparatus further comprises a machine-readable medium storing instructions readable and executable by the processor to cause the processor to process a request issued via the computing system for the processor to cause a memory operation to be performed in the memory device.

Abstract: Instructions may be provided to cause a computing device to receive authorisation data, the authorisation data indicating a policy; output a cryptographic challenge, the cryptographic challenge associated with the computing device and the policy; receive a response to the cryptographic challenge; receive an indication that a hardware change has occurred or a cover of the computing device has been opened; and in response to a determination, based on the received response, that the cryptographic challenge is passed, react to the indication according to the policy.

Abstract: In an example, a method is described. The method comprises receiving a log comprising information about a computing system. The log is sent by a computing device associated with the computing system. The computing device comprises a first identity bound to a third identity of a certificate authority (CA) and a second identity bound to the first identity. The method further comprises receiving a signature for the log. The method further comprises verifying a certificate indicative of the second identity having been certified. The method further comprises verifying the received signature.

Abstract: In an example there is provided a method, comprising generating a token in response to an interaction between a user device associated to a user and a service device associated to a service. The token comprises record data indicative of the interaction and verification data to verify the record data. The token is communicated to the user device. The token is stored at the service device. The verification data is generated on the basis of the record data and identification data associated to the user.