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Block Cipher Modes Of Operation
In cryptography, a block cipher mode of operation is an algorithm that uses a block cipher to provide information security such as confidentiality or authenticity. A block cipher by itself is only suitable for the secure cryptographic transformation (encryption or decryption) of one fixed-length group of bits called a block. A mode of operation describes how to repeatedly apply a cipher's single-block operation to securely transform amounts of data larger than a block. Most modes require a unique binary sequence, often called an initialization vector (IV), for each encryption operation. The IV has to be non-repeating and, for some modes, random as well. The initialization vector is used to ensure distinct ciphertexts are produced even when the same plaintext is encrypted multiple times independently with the same key. Block ciphers may be capable of operating on more than one block size, but during transformation the block size is always fixed. Block cipher modes oper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block Cipher
In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called ''blocks''. Block ciphers are specified cryptographic primitive, elementary components in the design of many cryptographic protocols and are widely used to encryption, encrypt large amounts of data, including in data exchange protocols. A block cipher uses blocks as an unvarying transformation. Even a secure block cipher is suitable for the encryption of only a single block of data at a time, using a fixed key. A multitude of block cipher modes of operation, modes of operation have been designed to allow their repeated use in a secure way to achieve the security goals of confidentiality and authentication, authenticity. However, block ciphers may also feature as building blocks in other cryptographic protocols, such as universal hash functions and pseudorandom number generators. Definition A block cipher consists of two paired algorithms, one for encryption, , and the othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciphertext Stealing
In cryptography, ciphertext stealing (CTS) is a general method of using a block cipher mode of operation that allows for processing of messages that are not evenly divisible into blocks without resulting in any expansion of the ciphertext, at the cost of slightly increased complexity. General characteristics Ciphertext stealing is a technique for encrypting plaintext using a block cipher, without padding the message to a multiple of the block size, so the ciphertext is the same size as the plaintext. It does this by altering processing of the last two blocks of the message. The processing of all but the last two blocks is unchanged, but a portion of the ''second''-last block's ciphertext is "stolen" to pad the last plaintext block. The padded final block is then encrypted as usual. The final ciphertext, for the last two blocks, consists of the partial penultimate block (with the "stolen" portion omitted) plus the full final block, which are the same size as the original plaint ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Organization For Standardization
The International Organization for Standardization (ISO ) is an international standard development organization composed of representatives from the national standards organizations of member countries. Membership requirements are given in Article 3 of the ISO Statutes. ISO was founded on 23 February 1947, and (as of November 2022) it has published over 24,500 international standards covering almost all aspects of technology and manufacturing. It has 809 Technical committees and sub committees to take care of standards development. The organization develops and publishes standardization in all technical and nontechnical fields other than electrical and electronic engineering, which is handled by the IEC.Editors of Encyclopedia Britannica. 3 June 2021.International Organization for Standardization" ''Encyclopedia Britannica''. Retrieved 2022-04-26. It is headquartered in Geneva, Switzerland, and works in 167 countries . The three official languages of the ISO are English, F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OCB Mode
Offset codebook mode (OCB mode) is an authenticated encryption mode of operation for cryptographic block ciphers. OCB mode was designed by Phillip Rogaway, who credits Mihir Bellare, John Black, and Ted Krovetz with assistance and comments on the designs. It is based on the '' integrity-aware parallelizeable mode'' (IAPM) of authenticated encryption by Charanjit S. Jutla. The ''OCB2'' version was proven insecure, while the original ''OCB1'' as well as ''OCB3'' from 2011 are still considered secure. Encryption and authentication OCB mode was designed to provide both message authentication and privacy. It is essentially a scheme for integrating a message authentication code (MAC) into the operation of a block cipher. In this way, OCB mode avoids the need to use two systems: a MAC for authentication and encryption for privacy. This results in lower computational cost compared to using separate encryption and authentication functions. There are three versions of OCB: OCB1, OCB2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IAPM (mode)
Integrity-aware parallelizable mode (IAPM) is a mode of operation for cryptographic block ciphers. As its name implies, it allows for a parallel mode of operation for higher throughput. Encryption and authentication At the time of its creation, IAPM was one of the first cipher modes to provide both authentication and privacy in a single pass. (In earlier authenticated encryption designs, two passes would be required to: one to encrypt, and the second to compute a MAC.) IAPM was proposed for use in IPsec. Other AEAD schemes also provide all of the single pass, privacy and authentication properties. IAPM has mostly been supplanted by Galois/counter mode. See also * OCB mode Offset codebook mode (OCB mode) is an authenticated encryption mode of operation for cryptographic block ciphers. OCB mode was designed by Phillip Rogaway, who credits Mihir Bellare, John Black, and Ted Krovetz with assistance and comments on th ... References {{Cryptography navbox , block , hash ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
