Abstract: Techniques are disclosed for securely managing data. In one example, a service provider receives user image data and user biometric data associated with a user. The service provider generates a user profile cryptographic key based on hashing this data, which may be associated with a user identifier. The service provider may further generate a public/private key pair associated with the user identifier. The public key and the user profile cryptographic key are stored, in association with the user identifier, to a consortium blockchain network. The service provider then receives a request, signed with the private key, to store a document in association with the user identifier. The service provider generates a document cryptographic key of the document, and executes a request to store the document cryptographic key to the blockchain in association with the user profile cryptographic key, the request verified using the public key.

Abstract: Techniques are disclosed for securely managing data. In one example, a service provider receives user image data and user biometric data associated with a user. The service provider generates a user profile cryptographic key based on hashing this data, which may be associated with a user identifier. The service provider may further generate a public/private key pair associated with the user identifier. The public key and the user profile cryptographic key are stored, in association with the user identifier, to a consortium blockchain network. The service provider then receives a request, signed with the private key, to store a document in association with the user identifier. The service provider generates a document cryptographic key of the document, and executes a request to store the document cryptographic key to the blockchain in association with the user profile cryptographic key, the request verified using the public key.

Abstract: A magnetoresistive medium (1) includes a substrate (2) which has been treated to provide a miscut vicinal surface (3) in the form of terraces (4) and steps (5) of atomic and nanometer scale. There are discrete separated spacer nanowires (7) provided by an intermediate partial spacer film on each terrace (4) against each step (5). A further main film (11) provides main nanowires (10(a), 10(b)). A thin protective layer (15) covers the main nanowires (10(a), 10(b)) which form two separate subsets of main nanowires with different exchange interaction with the substrate and thus a different response to an external magnetic field. In use, when an external magnetic field (H) is applied the response of the main nanowires (10(a), 10(b)) changes as the exchange coupling with the substrate (2) varies and the magnetisation on the main nanowires (10(a), 10(b)) change. This is shown by the arrows while prior to the application of the external magnetic field, they might, for example, be aligned.