Seagate Technology Incorporated

The Boeing Company

Donald Preston Matthews, Jr

Laszlo Hars

Monty Aaron Forehand

Jon David Trantham

Robert Wayne Moss

Navneeth Kankani

Rodney Virgil Bowman

Donald Rozinak Beaver

David O Sluiter

Charles William Thiesfeld

William Preston Goodwill

Tong Shirh Stone

Paul J Lemmon

A method of providing security in a computer system includes producing a plurality of sub-keys from key material and a respective address of a memory location in a memory and possibly other information. The method may include mixing the sub-keys together using a binary tree of exclusive-or operations, and to produce an intermediate result. The method may include performing a scrambling operation on the intermediate result to produce a key with which a block of ciphertext may be produced. And the method may include performing a write operation to write the block of ciphertext at the memory location having the respective address. In this regard, the memory may include a window of memory locations each of which stores a respective block of ciphertext produced with a respective key that changes from memory location to memory location.

Address-dependent key generator by XOR tree

An apparatus can include at least one test circuit configured to determine if bits sampled at a sample frequency from at least one bit generator are random, and a circuit configured to adjust the sample frequency if the at least one test circuit determines that the sampled bits are not random. The apparatus can be a random number generator. A method may include sampling bits at a first sample frequency, and sampling bits at a second sample frequency if the sampled bits associated with the first sample frequency are not random.

Active test and alteration of sample times for a ring based random number generator

Method and apparatus for sanitizing a memory using bit-inverted data. In accordance with various embodiments, a memory location is sanitized by sequential steps of reading a bit value stored in a selected memory cell of the memory, inverting the bit value, and writing the inverted bit value back to the selected memory cell. The memory cell may be erased between the reading and writing steps, as well as after the writing step. Random bit values may be generated and stored to the memory cell, and run-length limited constraints can be used to force bit-inversions.

Memory sanitation using bit-inverted data

The disclosure is related systems and methods for using operation durations of a data storage medium to generate random numbers. In one embodiment, a device may comprise a random number generator circuit configured to store a value representing a duration of an operation on the data storage medium, and generate a random number based on the value. Another embodiment may be a method comprising recording durations of access operations to a data storage medium, and generating a random number based on the durations.

Using memory access times for random number generation

Method and apparatus for the non-destructive, selective purging of data from a non-volatile memory. In accordance with various embodiments, multiple copies of a selected set of confidential user data having a common logical address are stored to a confidential data portion of a non-volatile memory so that each copy is in a different location within the confidential data portion. A nondestructive purge of all said copies from the confidential data portion is carried out responsive to an externally supplied selective purge command so that all said copies are erased and other, non-purged confidential user data remain stored in the confidential data portion.

Selective purge of confidential data from a non-volatile memory

A method for providing security for plaintext data being transferred between units in a computer system includes steps of dividing a memory into a series of addressable locations, each of the addressable locations having an address at which can be stored version information, a data authentication tag, and ciphertext corresponding to the plaintext. The system retrieves the ciphertext, the version information, and the data authentication tag, and generates encryption keys for decrypting the information stored at the address. If the data authentication tag indicates the plaintext data are valid, then the system provides the decrypted plaintext to the requestor, or encrypts new plaintext data and stores the corresponding ciphertext with new authentication and version information at the first address.

Secure memory transaction unit

An apparatus includes: a plurality of bit producing circuits; a controller setting a sample frequency at which bits from the bit producing circuits are sampled; and a plurality of test circuits determining if bits sampled from each of the bit producing circuits are random, wherein the controller adjusts the sample frequency if the test circuits determine that the sampled bits are not random. A method performed by the apparatus is also included.

Method and apparatus for encrypting and storing data to provide data security and memory cell bit wear leveling. In accordance with various embodiments, input data are provided for writing to a target page of memory in a storage array. A seed value is derived from a count value indicative of a number of times a write access has occurred on the target page of memory. A block encryption routine is applied to the input data using the seed value to generate encrypted output data that are thereafter written to the target page.

Data encryption to provide data security and memory cell bit wear leveling

Method and apparatus for compressing data. In accordance with various embodiments, an input string of data bits is received and arranged into fixed-sized chunks. Multiple successive chunks of the input string are compared to previously received chunks of the input string during a single clock cycle. At least two alternative encoding solutions are identified based on matches obtained during said comparison. The input string is compressed to form a compressed output string using a selected one of the at least two alternative encoding solutions that achieves a fewer number of bits in said output string.

Evaluating alternative encoding solutions during data compression

An apparatus comprises at least one port for coupling signals to the apparatus, a mode selector for setting the apparatus to a normal mode or a debug mode, and a port control for controlling access to secure information in the apparatus through the port in accordance with the selected mode. A method for controlling access to the port is also provided.

Growing community of inventors

Longmont, CO, United States of America

Donald Preston Matthews, Jr