Abstract: The aim of the invention is to provide a means of encrypting company-related data which also ensures that the data can be reproduced if the key is lost. To this end, the invention provides a method or an information processing system in which a key for a symmetrical encryption method is allocated to a user (4) for encrypting the data. Allocation information associating the key with the predetermined data to be encrypted and/or the user (4) is stored and can only be accessed by an authorised third party. If necessary, the key used for the particular data can be determined and the encrypted data reproduced, i.e. rendered readable, by this authorized third party. The allocation information, associating a particular key with an element identifying the predetermined data or a user identifier, can be stored in the information processing system in a predetermined manner or be created following a request for the allocation of a key.

Abstract: A method in which a user first receives from a Trust Center a generated, personalized, and certified key pair as well as components for producing encryption pairs. The user at any time himself produces an encryption key pair, marks the public part of this pair using the secret signature key relinquished to him, and transmits the result to the Trust Center, where the result is assigned to the user using the certified public part of the signature key pair.

Abstract: The aim of the invention is to provide a means of encrypting company-related data which also ensures that the data can be reproduced if the key is lost. To this end, the invention provides a method or an information processing system in which a key for a symmetrical encryption method is allocated to a user (4) for encrypting the data. Allocation information associating the key with the predetermined data to be encrypted and/or the user (4) is stored and can only be accessed by an authorised third party. If necessary, the key used for the particular data can be determined and the encrypted data reproduced, i.e. rendered readable, by this authorized third party. The allocation information, associating a particular key with an element identifying the predetermined data or a user identifier, can be stored in the information processing system in a predetermined manner or be created following a request for the allocation of a key.