摘要:
A system and method for coding data to help resist differential attacks. Data in m columns may be initialized to an initialized value. One new column of data may be mixed with a new input word and input to an advanced mixer. The advanced mixer may include linear mixing having indexed bytes and performing of exclusive-OR operation and transposing. An output of the advanced mixer may be a new m column state. A value of m could be 0 through 30. The value of m may have a preferred range of 27 through 36. Systems to implement the foregoing method are also described.
摘要:
A system and method for coding data to help resist differential attacks. Data in m columns may be initialized to an initialized value. One new column of data may be mixed with a new input word and input to an advanced mixer. The advanced mixer may include linear mixing having indexed bytes and performing of exclusive-OR operation and transposing. An output of the advanced mixer may be a new m column state. A value of m could be 0 through 30. The value of m may have a preferred range of 27 through 36. Systems to implement the foregoing method are also described.
摘要:
A method and apparatus for an advanced symmetric key cipher for encryption and decryption, using a block cipher algorithm. Different block sizes and key sizes are supported, and a different sub-key is used in each round. Encryption is computed using a variable number of rounds of mixing, permutation, and key-dependent substitution. Decryption uses a variable number of rounds of key-dependent inverse substitution, inverse permutation and inverse mixing. The variable length sub-keys are data-independent, and can be precomputed.
摘要:
The present invention provides a technique, system, and computer program for a symmetric key block cipher. Variable block sizes and key sizes are supported, as well as a variable number of rounds. The cipher uses multiple stages of processing, where the stages have different structures and different subround functions, to provide excellent resistance to both linear and differential attacks. Feistel Type-3 networks are used, with different networks during different stages. The number of rounds may vary among stages. Subkeys are used in some, but not all, stages. The variable-length keys can be precomputed. A novel manner of using multiplication in a cipher is defined.
摘要:
The present invention provides a technique, system, and computer program for a symmetric key block cipher. This cipher uses multiple stages with a modified Type-3 Feistel network, and a modified Unbalanced Type-1 Feistel network in an expansion box forward function. The cipher allows the block size, key size, number of rounds of expansion, and number of stages of ciphering to vary. The modified Type-3 cipher modifies the word used as input to the expansion box in certain rounds, to speed the diffusion properties of the ciphering. The modified Type-3 and Type-1 ciphers are interleaved, and provide excellent resistance to both linear and differential attacks. The variable-length subkeys and the S-box can be precomputed. A minimal amount of computer storage is required to implement this cipher, which can be implemented equally well in hardware or software (or some combination thereof).
摘要:
The present invention provides a technique, system, and computer program for a symmetric key block cipher. Variable block sizes and key sizes are supported, as well as a variable number of rounds. The cipher uses multiple stages of processing, where the stages have different structures and different subround functions, to provide excellent resistance to both linear and differential attacks. Feistel Type-1 and Type-3 are both used, each during different stages. The number of rounds may vary among stages. Subkeys are used in some, but not all, stages. The variable-length keys can be precomputed. A novel manner of using data-dependent rotation in a cipher is defined.
摘要:
A method and apparatus for an advanced byte-oriented symmetric key cipher for encryption and decryption, using a block cipher algorithm. Different block sizes and key sizes are supported, and a different sub-key is used in each round. Encryption is computed using a variable number of rounds of mixing, permutation, and key-dependent substitution. Decryption uses a variable number of rounds of key-dependent inverse substitution, inverse permutation, and inverse mixing. The variable length sub-keys are data-independent, and can be precomputed.
摘要:
A method for processing a memory page, the method includes: retrieving, in response to a request to provide a first memory page to a processor, first memory page metadata associated with first memory page address information; wherein the first memory page address information is stored in a memory page table; and performing a page operation in response to the memory page metadata; wherein the page operation is selected from a group consisting of compression, cryptography, searching a page for a virus signature, searching a page for digital right management signature, error correction code verification, error correction code addition.
摘要:
An access control system and method includes a risk index module which computes a risk index for a dimension contributing to risk. A boundary range defined for a parameter representing each risk index such that the parameter above the range is unacceptable, below the range is acceptable and in the range is acceptable with mitigation measures. A mitigation module determines the mitigation measures which reduce the parameter within the range by mapping the effectiveness of performing the mitigation measures to determine a residual risk after a mitigation measure has been implemented.
摘要:
A method of performing biometric authentication of a person's identity including a biometric template prior to storing it in a biometric database. The encryption algorithm encrypts the biometric template using a pass-phrase, known only to the individual, to generate the cryptographic key used to store and retrieve the biometric template. When an individual wishes to access a secured resource, he must be authenticated by providing an identifier which is used to retrieve the appropriate record. He must also provide the correct password to allow the system to decrypt the model.