Data on a primary data volume is restored by generating an image of the primary data volume at a specified point-time based on data stored on a backup data volume, where the data stored on the backup data volume includes data written to the primary data volume and stamps to indicate when the data was...http://www.google.co.uk/patents/US7778958?utm_source=gb-gplus-sharePatent US7778958 - Recovery of data on a primary data volume
