Patent ID: 7921301

Claim:
A method for obscuring data in memory, comprising: storing an identifier in first and second memories, wherein said identifier is associated with a controller; storing a first scrambling key in said second memory; determining, by said controller, whether a power outage is indicated, wherein said controller comprises a write cache; reading first original data from the write cache, wherein said first original data includes a first information and a first address; scrambling said first original data as indicated by said first scrambling key; determining from said first scrambling key a second pair of values comprising a designation of bit locations of a third bit and a fourth bit of said first original data, in response to determining that said power outage is indicated, storing said scrambled first original data in said first memory; wherein said first memory is associated with said controller, wherein said scrambling includes determining from said first scrambling key at least a first pair of values comprising a designation of bit locations of a first bit and a second bit of said first original data, and operating on said first original data to obtain said scrambled first original data, wherein said operating includes, with respect to said first original data, swapping a value of said first bit designated by said first scrambling key and a value of said second bit designated by said first scrambling key, wherein said swapping a value of said first bit designated by said first scrambling key and a value of said second bit designated by said first scrambling key provides first partially scrambled data, and wherein said operating on said first original data to obtain said scrambled first original data further includes, with respect to said first partially scrambled data, swapping a value of said third bit designated by said first scrambling key and a value of said fourth bit designated by said first scrambling key to obtain one of second partially scrambled data and said first scrambled data.