Results 81 to 90 of about 164 (126)

Secure Quaternion Feistel Cipher for DICOM Images

IEEE Transactions on Image Processing, 2019
An improved and extended version of a quaternion-based lossless encryption technique for digital image and communication on medicine (DICOM) images is proposed. We highlight and address several security flaws present in the previous version of the algorithm originally proposed by Dzwonkowski et al. (2015).
Mariusz Dzwonkowski, Roman Rykaczewski
openaire   +2 more sources

On Lai–Massey and quasi-Feistel ciphers

Designs, Codes and Cryptography, 2010
For finite sets \(\mathcal{X}\), \(\mathcal{Y}\) a combiner over \((\mathcal{X},\mathcal{Y})\) is a parameterized family \(\Gamma = {\{ {\Gamma _z}\} _{z \in \mathcal{Y}}}\) of quasigroups \({\Gamma _z}:{\mathcal{X}^2} \to \mathcal{X}\), denote \({\Gamma _z}(x,y) = \Gamma \left[\left[ {x*y|z} \right]\right]\). Let \(b > 1\), \(r > 1\) be fixed integers,
Yun, Aaram, Park, Je Hong, Lee, Jooyoung
openaire   +2 more sources

Information leakage of Feistel ciphers

IEEE Transactions on Information Theory, 2001
Summary: The author examines the information leakage between sets of plaintext and ciphertext bits in symmetric-key block ciphers. The paper demonstrates the effectiveness of information leakage as a measure of cipher security by relating information leakage to linear cryptanalysis and by determining a lower bound on the amount of data required in an ...
openaire   +2 more sources

Quasigroup Representation of Some Feistel and Generalized Feistel Ciphers

2013
There are several block ciphers designed by using Feistel networks or their generalization, and some of them allow to be represented by using quasigroup transformations, for suitably defined quasigroups. We are interested in those Feistel ciphers and Generalized Feistel ciphers whose round functions in their Feistel networks are bijections.
Mileva, Aleksandra, Markovski, Smile
openaire   +1 more source

Balanced Feistel Ciphers, First Properties

2017
Feistel ciphers are named after Horst Feistel who studied these schemes in the 1960s. In this chapter, we will only present classical Feistel ciphers, i.e. balanced Feistel ciphers with the ⊕ group law (Xor). In Chaps. 8, 9 and 10, we will see that there are many variants of these ciphers.
Valerie Nachef, Jacques Patarin, Emmanuel Volte   +2 more
openaire   +1 more source

Generic Attacks on Expanding Feistel Ciphers

2017
“Generic” Unbalanced Feistel Ciphers with Expanding Functions are Unbalanced Feistel Ciphers with truly random internal round functions from n bits to (k − 1)n bits with k ≥ 3. From a practical point of view, an interesting property of these schemes is that since n < (k − 1)n and n can be small (8 bits for example), it is often possible to store these ...
Valerie Nachef, Jacques Patarin, Emmanuel Volte   +2 more
openaire   +1 more source

Generic Attacks on Contracting Feistel Ciphers

2017
This chapter deals with generic attacks on unbalanced Feistel ciphers with contracting functions. These ciphers are used to construct pseudo-random permutations from kn bits to kn bits by using r pseudo-random functions from (k − 1)n bits to n bits. The study concerns KPA and NCPA against these schemes with less than 2 kn plaintext/ciphertext pairs and
Valerie Nachef, Jacques Patarin, Emmanuel Volte   +2 more
openaire   +1 more source

Improved Integral Attack on Generalized Feistel Cipher

2020
Division property is a generalized integral property proposed by Todo in Eurocrypt 2015. Utilizing automated tools such as SAT and MILP, the complexity to search for integral distinguisher by division property was greatly reduced. Based on division property and automated tools, Derbez et al.
Zhichao Xu, Hong Xu, Xuejia Lai
openaire   +1 more source

Generic Attacks on Generalized Feistel Ciphers

2017
Type-1, type-2 and type-3 and alternating Feistel schemes, are described by Zhen, Matsumoto, and Imai (On the construction of block ciphers provably secure and not relying on any unproved hypotheses, Springer, Heidelberg, 1990, pp. 461–480) (see also Hoang and Rogaway, On generalized Feistel networks, Springer, Heidelberg, 2010, pp. 613–630).
Valerie Nachef, Jacques Patarin, Emmanuel Volte   +2 more
openaire   +1 more source

Generic Attacks on Classical Feistel Ciphers

2017
In this chapter, we will give a complete description of best known attacks on classical Feistel ciphers.
Valerie Nachef, Jacques Patarin, Emmanuel Volte   +2 more
openaire   +1 more source