SOBER

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In cryptography, SOBER is a family of stream ciphers initially designed by Greg Rose of QUALCOMM Australia starting in 1997. The name is a contrived acronym for Seventeen Octet Byte Enabled Register. Initially the cipher was intended as a replacement for broken ciphers in cellular telephony. The ciphers evolved, and other developers (primarily Phillip Hawkes) joined the project.

Contents

SOBER was the first cipher, with a 17-byte linear-feedback shift register (LFSR), a form of decimation called stuttering, and a nonlinear output filter function. The particular configuration of the shift register turned out to be vulnerable to "guess and determine" attacks.

SOBER-2 changed the position of the feedback and output taps to resist the above attacks.

S16 was an expansion to 16-bit words rather than bytes, with an expected increase of security.

Adaptions for and since NESSIE

For the NESSIE call for new cryptographic primitives, three new versions called the t-class were developed; SOBER-t8 was virtually identical to SOBER-2 but did not have sufficient design strength for NESSIE submission; SOBER-t16 and SOBER-t32 were submitted. t32 was a further expansion to 32-bit words, while both ciphers had a more efficient method of computing the linear feedback.

Subsequent to NESSIE, SOBER-128 was designed to take into account what had been learned. The stuttering was dropped because it added too little strength for the overhead, and the nonlinear output function was strengthened. As a stream cipher, SOBER-128 remains unbroken. The message authentication capability that was added at the same time was trivially broken.

Mundja
An integrated message authentication feature based on SHA-256 that was designed to be added to stream ciphers such as SOBER-128.
Turing
Named after Alan Turing, shares the LFSR design of SOBER-128, but has a block-cipher-like output filter function with key-dependent S-boxes, and remains unbroken subject to a minor usage constraint.
NLS
Short for Non-Linear SOBER, it was submitted to the European eSTREAM project. It uses nonlinearity for the shift register, and simplifies the output filter for increased performance, using Mundja for message authentication. SSS, for Self-Synchronizing SOBER, was also submitted but has very little relationship to the other SOBER ciphers, and was quickly broken.
Shannon
Named after Claude Shannon, shortens the register to 16 32-bit words, and has completely new feedback and output filter tap positions. It incorporates a new and more efficient message authentication mechanism.
Boole
Named after George Boole, [1] is a family of combined hash functions and stream ciphers that were developed for submission to the NIST call for development of an advanced hash standard, but were withdrawn [2] when a collision was discovered. [3]

Related Research Articles

In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called blocks. They are specified elementary components in the design of many cryptographic protocols and are widely used to the encryption of large amounts of data, including data exchange protocols. It uses blocks as an unvarying transformation.

In cryptography, RC4 is a stream cipher. While it is remarkable for its simplicity and speed in software, multiple vulnerabilities have been discovered in RC4, rendering it insecure. It is especially vulnerable when the beginning of the output keystream is not discarded, or when nonrandom or related keys are used. Particularly problematic uses of RC4 have led to very insecure protocols such as WEP.

Stream cipher Type of symmetric key cipher

A stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream (keystream). In a stream cipher, each plaintext digit is encrypted one at a time with the corresponding digit of the keystream, to give a digit of the ciphertext stream. Since encryption of each digit is dependent on the current state of the cipher, it is also known as state cipher. In practice, a digit is typically a bit and the combining operation is an exclusive-or (XOR).

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 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.

Articles related to cryptography include:

Cryptographic hash function Hash function that is suitable for use in cryptography

A cryptographic hash function (CHF) is a mathematical algorithm that maps data of an arbitrary size to a bit array of a fixed size. It is a one-way function, that is, a function for which it is practically infeasible to invert or reverse the computation. Ideally, the only way to find a message that produces a given hash is to attempt a brute-force search of possible inputs to see if they produce a match, or use a rainbow table of matched hashes. Cryptographic hash functions are a basic tool of modern cryptography.

CRYPTREC is the Cryptography Research and Evaluation Committees set up by the Japanese Government to evaluate and recommend cryptographic techniques for government and industrial use. It is comparable in many respects to the European Union's NESSIE project and to the Advanced Encryption Standard process run by National Institute of Standards and Technology in the U.S.

In computer science and cryptography, Whirlpool is a cryptographic hash function. It was designed by Vincent Rijmen and Paulo S. L. M. Barreto, who first described it in 2000.

In cryptography, SAFER is the name of a family of block ciphers designed primarily by James Massey on behalf of Cylink Corporation. The early SAFER K and SAFER SK designs share the same encryption function, but differ in the number of rounds and the key schedule. More recent versions — SAFER+ and SAFER++ — were submitted as candidates to the AES process and the NESSIE project respectively. All of the algorithms in the SAFER family are unpatented and available for unrestricted use.

SOBER-128 is a synchronous stream cipher designed by Hawkes and Rose (2003) and is a member of the SOBER family of ciphers. SOBER-128 was also designed to provide MAC functionality.

Turing is a stream cipher developed by Gregory G. Rose and Philip Hawkes at Qualcomm for CDMA.

A nonlinear-feedback shift register (NLFSR) is a shift register whose input bit is a non-linear function of its previous state.

VEST

VEST ciphers are a set of families of general-purpose hardware-dedicated ciphers that support single pass authenticated encryption and can operate as collision-resistant hash functions designed by Sean O'Neil, Benjamin Gittins and Howard Landman. VEST cannot be implemented efficiently in software.

Grain is a stream cipher submitted to eSTREAM in 2004 by Martin Hell, Thomas Johansson and Willi Meier. It has been selected for the final eSTREAM portfolio for Profile 2 by the eSTREAM project. Grain is designed primarily for restricted hardware environments. It accepts an 80-bit key and a 64-bit IV. The specifications do not recommended a maximum length of output per pair. A number of potential weaknesses in the cipher have been identified and corrected in Grain 128a which is now the recommended cipher to use for hardware environments providing both 128bit security and authentication.

In cryptography, Galois/Counter Mode (GCM) is a mode of operation for symmetric-key cryptographic block ciphers which is widely adopted for its performance. GCM throughput rates for state-of-the-art, high-speed communication channels can be achieved with inexpensive hardware resources. The operation is an authenticated encryption algorithm designed to provide both data authenticity (integrity) and confidentiality. GCM is defined for block ciphers with a block size of 128 bits. Galois Message Authentication Code (GMAC) is an authentication-only variant of the GCM which can form an incremental message authentication code. Both GCM and GMAC can accept initialization vectors of arbitrary length.

ORYX is an encryption algorithm used in cellular communications in order to protect data traffic. It is a stream cipher designed to have a very strong 96-bit key strength with a way to reduce the strength to 32-bits for export. However, due to mistakes the actual strength is a trivial 16-bits and any signal can be cracked after the first 25–27 bytes.

Crypto-1

Crypto1 is a proprietary encryption algorithm and authentication protocol created by NXP Semiconductors for its MIFARE Classic RFID contactless smart cards launched in 1994. Such cards have been used in many notable systems, including Oyster card, CharlieCard and OV-chipkaart.

SHA-3 is the latest member of the Secure Hash Algorithm family of standards, released by NIST on August 5, 2015. Although part of the same series of standards, SHA-3 is internally different from the MD5-like structure of SHA-1 and SHA-2.

The following outline is provided as an overview of and topical guide to cryptography:

T32 may refer to:

References

  1. ↑ http://seer-grog.net/BoolePaper.pdf [ bare URL PDF ]
  2. ↑ "Archived copy" (PDF). Archived from the original (PDF) on 2009-07-13. Retrieved 2009-10-26.{{cite web}}: CS1 maint: archived copy as title (link)
  3. ↑ http://ehash.iaik.tugraz.at/uploads/0/0b/BooleCollision.txt [ bare URL plain text file ]
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