摘要 |
A method and apparatus that allows renewal of encoded data in a long-term storage. Original user data 200 is encrypted to form encrypted data 211 which can be accessed using one or more encryption secrets 213 stored separately, and optionally validated using context data 212. At renewal, the encrypted data 211, the context data 212, and the or each encryption secret 213 are combined to form a first encryption layer 210 and the first encryption layer 210 is itself encrypted to form the encrypted data 221 of an immediately succeeding second encryption layer 220. The encrypted data 221 of this second encryption layer 220 is accessible with a renewed encryption secret 223, and optionally is validated by context data 222 such as a time stamp and trusted signature. The method may be repeated recursively, forming third and subsequent encryption layers 230 at each renewal. |