A method and apparatus for obscuring data held on a storage device associated with a storage system controller are provided. Data is obscured by swapping bit values according to a scrambling key, before the unit of data is stored on the storage device. Furthermore, multiple swaps or translations of bit values can be performed in sequence on a single unit of data. In order to descramble a unit of data, the translations of bit values applied during scrambling are performed in reverse order. Alternatively or in addition, data can be obscured by scrambling the bit values of an address associated with a unit of data.