A System and a Method for Management of Confidential Data

摘要

A system and a method for managing confidential data in a cloud service is provided. The system comprises a cryptographic key service comprising two or more cryptographic key servers, Si, each being arranged to compute file encryption keys, kj, on the basis of information regarding data and using one or more cryptographic keys, Kj. The cryptographic keys, Kj, are secretly shared among the cryptographic key servers, Si, and none of the cryptographic key servers, Si, possesses knowledge of all of the cryptographic keys, Kj. A single point of trust at the cryptographic key service is avoided.

主权项

1. A system for management of confidential data, the system comprising:
a cloud service for holding encrypted data, a cryptographic key service comprising two or more cryptographic key servers, Si, each cryptographic key server, Si, being arranged to generate one or more cryptographic key(s), Kj, and to compute one or more file encryption key(s), kj, on the basis of information regarding data to be encrypted or decrypted, and using the cryptographic key(s), Kj, the cryptographic key(s), Kj, and the file encryption key(s), kj, thereby being created at the cryptographic key servers, Si, and one or more client devices, each client device being arranged to communicate with the cloud service and/or with the cryptographic key service in order to obtain encryption and/or decryption of data, and in order to provide encrypted data to the cloud service and/or retrieve decrypted data from the cloud service, using two or more file encryption keys, kj, computed by the cryptographic key servers, Si, wherein the cryptographic key servers, Si, of the cryptographic key service are further arranged to generate one or more new cryptographic key(s), Kj′, and wherein the system is further arranged to reencrypt one or more encrypted data files stored in the cloud service, using the new cryptographic keys, Kj′.