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.

Abstract: According to aspects of the present disclosure, there is provided methods and devices for verifying integrity of a remote device, including a method comprising generating a first nonce value, transmitting the first nonce value, receiving a message from the remote device, the message comprising measurements of a configuration of the remote device and a cryptographic signature based on a private key of a public-private key pair of the remote device and a second nonce value, determining that the second nonce value was generated based on the first nonce value, and verifying the cryptographic signature based on the second nonce value and a public key of the public-private key pair of the remote device.

Abstract: In an example there is provided a method for initiating an auxiliary access protocol in an authentication session. The method comprises providing attestation data attesting to a cause of an outcome of an authentication attempt in an authentication session, accessing a policy to initiate an auxiliary access protocol, determining if the attestation data fulfils a criterion according to the policy and initiating the auxiliary access protocol on the basis of said determination.

Abstract: In an example a method includes retrieving, from a persistent memory, a previously-identified counter value corresponding to an iteration of a prime number generation procedure that previously produced a verified prime number. The method further includes re-generating, using processing circuitry implementing a deterministic prime number calculator and with the previously-identified counter value as an input to the deterministic prime number calculator, the verified prime number.

Abstract: In an example, a method includes obtaining an initial seed, a public parameter associated with a processing apparatus and an indication of a state of the processing apparatus. The method may further include generating, by the processing apparatus, a key corresponding to the state of the processing apparatus. The state of the processing apparatus may be based on a combination of the initial seed, the public parameter and the indication of the state.

Abstract: In an example, a method includes receiving a signed message generated by a computing device associated with a private key and a public key. The signed message includes an input message signed with the private key. The method further includes generating, using processing circuitry, a candidate public key based on the input message and the signed message using a public key recovery procedure. The method further includes determining the public key associated with the computing device based on an indication as to whether or not the candidate public key corresponds to the public key associated with the computing device.

Abstract: A method of operating a service provider server and a computing device to provide anonymous service access. For the service provider server, the method comprises: receiving a service message from a computing device; and determining whether to send a service response message, and if so sending a service response message. The service message includes a pseudonym associated with the computing device, service data and a signature on the pseudonym generated by either the service provider server or an identity manager. The service response message is broadcast by the service provider server or transmitted to the identity manager.

Abstract: A method comprising: receiving, by a blockchain maintainer, a client request for a cryptographic token, the cryptographic token to allow the client to access a particular service from a service provider; processing, by the blockchain maintainer, the request using a blockchain smart contract to determine if the client request is valid; if the client request is determined to be valid, including the client request in the blockchain; generating, by a token issuer, the requested cryptographic token in response to inclusion of the valid client request in the blockchain; and issuing the generated cryptographic token to the client.

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: There is disclosed a method for encrypting data representing a rendering task, the method comprising segmenting the data to form multiple variably sized segments, wherein each segment comprises a payload, and a footer portion comprising at least a footer size section indicating the size of a footer encoding the size of a subsequent segment, and encrypting each segment using data associated with that segment and the rendering task.

Abstract: An apparatus is disclosed. The apparatus may comprise a storage medium to store: a first data structure to receive a first plurality of numerical identifiers, each numerical identifier of the first plurality of numerical identifiers corresponding to a respective signal received during a first defined time interval; and a second data structure to receive a second plurality of numerical identifiers, each numerical identifier of the second plurality of numerical identifiers corresponding to a respective signal received during a second defined time interval, wherein the first defined time interval is earlier in time than the second defined time interval. The apparatus may comprise a processor.