1. A method for execution by one or more processing modules of one or more computing devices, the method comprises: segmenting a data partition into a plurality of data segments; and for a data segment of the plurality of data segments: dividing the data segment into a set of data sub-segments; generating a set of sub keys for the set of data sub-segments based on a master key; encrypting the set of data sub-segments using the set of sub keys to produce a set of encrypted data sub-segments; aggregating the set of encrypted data sub-segments into encrypted data; generating a masked key based on the encrypted data and the master key; and combining the encrypted data and the masked key to produce an encrypted data segment.