US 9,811,476 B2
Encryption and recording apparatus, encryption and recording system, and encryption and recording method
Takuji Maeda, Osaka (JP); Shinji Inoue, Osaka (JP); and Yoshikazu Katoh, Osaka (JP)
Assigned to Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Appl. No. 14/769,615
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Feb. 6, 2014, PCT No. PCT/JP2014/000640
§ 371(c)(1), (2) Date Aug. 21, 2015,
PCT Pub. No. WO2014/132572, PCT Pub. Date Sep. 4, 2014.
Claims priority of application No. 2013-038394 (JP), filed on Feb. 28, 2013.
Prior Publication US 2016/0004646 A1, Jan. 7, 2016
Int. Cl. H04L 9/32 (2006.01); G06F 12/14 (2006.01); G06F 21/62 (2013.01); H04L 9/14 (2006.01); H04L 9/08 (2006.01); G06F 12/02 (2006.01)
CPC G06F 12/1408 (2013.01) [G06F 12/0238 (2013.01); G06F 21/62 (2013.01); H04L 9/088 (2013.01); H04L 9/0897 (2013.01); H04L 9/14 (2013.01); G06F 2212/1052 (2013.01); G06F 2212/202 (2013.01); H04L 2209/605 (2013.01)] 6 Claims
OG exemplary drawing
 
1. An encryption and recording apparatus storing data, the encryption and recording apparatus comprising:
a first nonvolatile memory;
a second nonvolatile memory; and
an encryption and decryption controller configured to encrypt and write the data to the second nonvolatile memory, and read the encrypted data from the second nonvolatile memory and decrypt the encrypted data, wherein
the encryption and decryption controller is configured to:
manage an area included in the second nonvolatile memory on a per-block basis, and manage an association between a block and a block-unique key using key management information stored in the first nonvolatile memory;
when receiving a write indication for writing the data from an access apparatus external to the encryption and recording apparatus, receive the data and corresponding information associated with the data, encrypt the data using a plurality of block-unique keys associated with a plurality of blocks included in the second nonvolatile memory, and write the data to the plurality of blocks; and
store the corresponding information in the key management information such that the corresponding information is associated with the plurality of block-unique keys,
the first nonvolatile memory includes a memory cell array in which memory cells are arranged in an array, the memory cells including:
a memory cell in a variable state, which has a resistance value which reversibly transitions among a plurality of variable resistance value ranges in response to application of different electrical signals; and
a memory cell in an initial state, which remains in the initial state unless a forming stress is applied, and has a resistance value in an initial resistance value range overlapping with none of the plurality of variable resistance value ranges, the forming stress being electrical stress for placing the memory cell in the initial state into the variable state,
the memory cell array can record first-type data and second-type data,
the first-type data is recorded, based on a difference for each of the memory cells as to whether the memory cell has a resistance value in the initial resistance value range or not,
the second-type data is recorded, based on a difference for each of the memory cells as to whether the memory cell has a resistance value in at least one of the plurality of variable resistance value ranges or not, rather than based on the difference as to whether the memory cell has a resistance value in the initial resistance value range or not,
the first-type data includes the plurality of block-unique keys, and
the data is encrypted using a password which is the corresponding information, prior to being transmitted together with the write indication from the access apparatus.