Counting Functions Satisfying a Higher Order Strict Avalanche Criterion

By guaranteeing that a single input bit flip substantially changes the ciphertext, this paper propose a unique cryptographic architecture to improve the StrictAvalanche Criterion (SAC) in speech ciphers and strengthen security against cryptanalytic attacks. By using XOR operations to cumulatively mix plaintext segmentswith various secret keys, the method introduces non-linearity to produce a uniform bit distribution. The primary benefit is in its capacity to generate a balancedavalanche effect with a lower computational complexity, beyond the constraints ofconventional techniques. The effectiveness of the approach was assessed throughrandom secret keys and mixing levels of 2, 4, and 8 quantifying performance usingstandard cryptographic analysis. With a bit change rate of 49.93% for mixing level2, increasing to 50.035% for mixing level 4, and stabilizing at 50.04% for mixing level8, the results show a nearly optimal SAC, verifying scalability and efficiency. Theseresults show that by attaining robust SAC with consistent randomization, the suggested cumulative XOR technique greatly improves voice encryption systems. Thestrategy is expected to help secure communication applications and offers a promising direction for future study into simple, scalable cryptographic solution and itsperformance.

The Substitution Box (S-box) is a fundamental nonlinear transformation utilized within cryptographic algorithms to map an input bit string into an output bit string. Due to the complexity and variability of cryptographic attacks, constructing S-boxes using traditional methods has proven challenging. However, recent advancements in optimization algorithms have provided new ideas for S-box construction. To address the difficulty of constructing high-performance S-boxes through traditional means, this paper proposes a design for an 8×8 S-box based on the improved sine-cosine algorithm. In this study, genetic algorithm's mutation and crossover operations are incorporated into the sine-cosine algorithm to optimize the initial S-box constructed using the improved Newton iterative method. The resulting S-box is then evaluated based on cryptographic criteria such as bijection, nonlinearity, strict avalanche criterion, bit-independent criterion, linear probability, and differential probability. Comparative analysis with several previous S-box generation methods demonstrates that the proposed S-box design exhibits superior cryptographic properties.

In this paper the authors present a statistical test for testing the strict avalanche criterion (SAC), a property that cryptographic primitives such as block ciphers and hash functions must have. Random permutations should also behave as good random number generators when, given any initial input, its output is considered part of a pseudorandom stream and then used as an input block to produce more output bits. Using these two ideal properties, we construct a test framework for cyptographic primitives that is shown at work on the block cipher TEA. In this way, we are able to distinguish reduced round versions of it from a random permutation.

A new S-box construction method meeting strict avalanche criterion

In this manuscript we present a novel method to design strong substitution Boxes based on chaos function and genetic algorithm techniques. Furthermore, we analyse the strength of the proposed S-Boxes. The proposed methodology is analyzed and tested for the following criteria: bijective property, nonlinearity, strict avalanche criterion, output bits independence criterion and equiprobable input/output XOR distribution. Numerical simulation and security analysis demonstrate that the scheme is practical in image encryption.

In this study the authors propose a new multivariate hash function with HAsh Iterative FrAmework framework which we call the hash function quadratic polynomials multiplying linear polynomials (QML). The new hash function is made of cubic polynomials which are the products of quadratic polynomials and linear polynomials. The authors design the quadratic-polynomial part of the compression function based on the centre map of the multivariate public key cryptosystem Matsumoto-Imai cryptosystem (MI). The hash function QML can keep the three cryptography properties and be immune to the pre-image attack, second pre-image attack, collision attack, differential attack and algebraic attack. The required memory storage is about 50% of the one which is built of the cubic polynomials and their coefficients are random. On the avalanche effect, by experiments the authors get the result that about one half of the output bits are different when one input bit is changed randomly. The one-round diffusion of the hash function QML is twice of that of Blake. Also the authors simplify the matrixes of the new hash function, analyse the rationality and show the comparable data. Finally, the authors give the advice to the parameters of the new hash function and summarise the paper.

The Strict Avalanche Criterion (SAC) is a measure of both confusion and diffusion, which are key properties of a cryptographic hash function. This work provides a working definition of the SAC, describes an experimental methodology that can be used to statistically evaluate whether a cryptographic hash meets the SAC, and uses this to investigate the degree to which compression function of the SHA-1 hash meets the SAC. The results (P < 0.01) are heartening: SHA-1 closely tracks the SAC after the first 24 rounds, and demonstrates excellent properties of confusion and diffusion throughout.

In modern cryptography, hash functions are considered as one of the key components for secure communication. They play a vital role in a wide range of applications such as ensuring the authentication and integrity of the data, in forensic investigation, password storage, random number generations for unique session keys, and for creating a unified view in blockchain. The Avalanche effect (also known as diffusion) is an important characteristic of a hash function where a minor change in the hash function’s input will result in a significantly different output. The absence of this property implies that the hash function is vulnerable to various attacks such as collision attack, length extension attack, and preimage attack. Through this research, we have investigated the Avalanche effect of sixteen hash functions and two hash-based applications, namely Hash-based Message Authentication Code (HMAC) and Public Key Cryptography Standards (PKCS). To measure the performance of these hash functions and hash-based applications, we have implemented a generic circuit using CrypTool for automating the simulation process for multiple trials. Simulation results indicate that around half of the inputs of each hash function failed to exhibit the Strict Avalanche Criterion (SAC) and, Bit Independence Criterion (BIC). Moreover, we ranked the hash functions based on Multi Criteria Decision Metrics (MCDM) using intermediate states of simulation results. Furthermore, a total of fifteen statistical tests were carried out to evaluate the randomization property of the hash functions using NIST (National Institute of Standards and Technology) toolkit. This study is aimed to open up a future scope of research to the need for improvement of various hash functions by analyzing the randomization and non-correlation properties of existing functions in terms of the Avalanche effect.

Quantum technology application is a rapidly developing discipline in future-generation research. It has grown its appeal due to several unique aspects which cannot be encountered in classical domains. Quantum properties can be used to create powerful and effective technology. The processing capability of a quantum computer is triggered by managing quantum particles in a quantum computer, which improves transformation in many domains. Quantum logic operations have the significant benefit of being reversible. Unlike classical irreversible processing, quantum logic gates are reversible and unitary, allowing input bits to be recovered via a one-to-one connection between input and output bits. In QCADesigner, as well as in the Quantum environment, different reversible logic gates may be constructed. Some other promising features include Superposition (Quantum Parallelism), Entanglement, etc. This study uses IBM quantum to create the QCA-based Majority voter gate.

A necessary and sufficient condition on the Walsh-spectrum of a boolean function is given, which implies that this function fulfills the Strict Avalanche Criterion. This condition is shown to be fulfilled for a class of functions exhibiting simple spectral symmetries. Finally, an extended definition of the Strict Avalanche Criterion is proposed and the corresponding spectral characterization is derived.KeywordsBoolean FunctionExhaustive SearchTruth TableSpectral CharacterizationSymmetry ReasonThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Ever since Baptista in 1998 introduced his cryptographic scheme utilizing the only in online version. ergodic property of chaotic maps which is able to produce different cipher values for the same plaintext within the same message, intense scrutiny has been given upon the design. The capability to do the above mentioned output is akin to the Vigenere cipher and thus has the capacity to render an attacker with infinitely many choices (theoretically speaking) or in cryptographic terms would render an attacker to have a set off possible ciphertexts that could all have the possibility to just be mapped to a unique plaintext. This makes it computationally infeasible for the attacker to re-construct the correct plaintext. The Baptista design has been attacked and repaired many times. Alvarez noticed the characteristic of the cryptosystem that generates a sequence which can be exploited by an attacker. The attack which is dubbed the one-time pad attack is akin to an attack upon a One-Time-Pad (OTP) cryptosystem that reuses its key. Since then, attempts were made to redefine the cryptosystem such that it would be resistant towards the attack. Most of the attempts failed due to either the repaired cryptosystem still generates an exploitable sequence or it is not invertible. In this work we pair the Baptista design with a concept taken from the Iterated Function Systems (IFS). Although we did not encompass the whole concept of iterating the IFS, it could be seen that this could be easily done with the same desirable results. Four main outcomes are discussed. Beginning with the discussion on the infeasibility of Alvarez’s one-time pad attack on the design, we then discuss the quantitative properties of the design in discussing its cryptographic properties namely the Maximum Deviation Factor (MDF), Correlation Coefficient Factor (CCF) and the Strict Avalanche Criterion (SAC). Each experimental result shows promising results for this new design.KeywordsCryptosystemStrict Avalanche Criterion (SAC)Iterated Function Systems (IFS)Chaotic MapsOne-time Pad (OTP)These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

This paper considers the basic $\mathcal{PULL}$ model of communication, in which in each round, each agent extracts information from few randomly chosen agents. We seek to identify the smallest amount of information revealed in each interaction (message size) that nevertheless allows for efficient and robust computations of fundamental information dissemination tasks. We focus on the Majority Bit Dissemination problem that considers a population of $n$ agents, with a designated subset of source agents. Each source agent holds an input bit and each agent holds an output bit. The goal is to let all agents converge their output bits on the most frequent input bit of the sources (the majority bit). Note that the particular case of a single source agent corresponds to the classical problem of Broadcast. We concentrate on the severe fault-tolerant context of self-stabilization, in which a correct configuration must be reached eventually, despite all agents starting the execution with arbitrary initial states. We first design a general compiler which can essentially transform any self-stabilizing algorithm with a certain property that uses $\ell$-bits messages to one that uses only $\log \ell$-bits messages, while paying only a small penalty in the running time. By applying this compiler recursively we then obtain a self-stabilizing Clock Synchronization protocol, in which agents synchronize their clocks modulo some given integer $T$, within $\tilde O(\log n\log T)$ rounds w.h.p., and using messages that contain $3$ bits only. We then employ the new Clock Synchronization tool to obtain a self-stabilizing Majority Bit Dissemination protocol which converges in $\tilde O(\log n)$ time, w.h.p., on every initial configuration, provided that the ratio of sources supporting the minority opinion is bounded away from half. Moreover, this protocol also uses only 3 bits per interaction.

This work presents the coder and decoder of block mBnB of the type 1B2B or Manchester. In the coder 1B2B each block/word of 1 input bit is coded in the block / word of 2 output bits. In the decoder 1B2B happen the inverse, each block of 2 input bits is newly converted in the original block of 1 output bit. The coder injects in the transmission line a number of 1’s exactly equal to the number of 0’s, what guarantees a DC constant component and maximizes the transitions number. The objective is to implement the pair coder and decoder 1B2B so that it improves the transmission quality and increases the information security. Keywords: Block codes, Digital systems, Transmission lines

The authors theoretically demonstrate the implementation of a low-power 4-state universal logic gate (NOR) using a linear array of three dipole-coupled magnetostrictive-piezoelectric multiferroic nanomagnets (e.g. Ni/PZT) with biaxial magnetocrystalline anisotropy. The two peripheral nanomagnets in the array encode the 4-state input bits in their magnetization orientations and the central nanomagnet's magnetization orientation represents the output bit. Numerical simulations are performed to confirm that the 4-state output bit is the Boolean NOR function of the two 4-state inputs bits when the array reaches its ground state. A voltage pulse alternating between −0.2 and +0.2 V, applied to the piezoelectric layer of the central nanomagnet, generates alternating tensile and compressive stress in its magnetostrictive layer. This drives the array to the correct ground state where dipole interaction between the magnets ensures that the output is the NOR function of the input. For the system considered, the gate operation is executed while dissipating only ∼33 000 kT (0.138 fJ) of energy.

With the growing availability of experimental loophole-free Bell tests1–5, it has become possible to implement a new class of device-independent random number generators whose output can be certified6,7 to be uniformly random without requiring a detailed model of the quantum devices used8–10. However, all these experiments require many input bits to certify a small number of output bits, and it is an outstanding challenge to develop a system that generates more randomness than is consumed. Here we devise a device-independent spot-checking protocol that consumes only uniform bits without requiring any additional bits with a specific bias. Implemented with a photonic loophole-free Bell test, we can produce 24% more certified output bits (1,181,264,237) than consumed input bits (953,301,640). The experiment ran for 91.0 h, creating randomness at an average rate of 3,606 bits s–1 with a soundness error bounded by 5.7 × 10−7 in the presence of classical side information. Our system allows for greater trust in public sources of randomness, such as randomness beacons11, and may one day enable high-quality private sources of randomness as the device footprint shrinks. Device-independent randomness expansion is demonstrated in an experiment that is secure in the presence of a classical eavesdropper who does not share any entanglement with the setup.