Modern Cryptographic Algorithms Research Articles

Secure method of communication using Quantum Key Distribution

Secure communication plays a vital role now-a-days. Modern-day secure communication is made possible via cryptography. Modern cryptographic algorithms are based on the process of factoring large integers into their primes, as they are intractable. But the cryptography nowadays is vulnerable to technological advances in computing power like quantum computing and evolution in math to quickly reverse one-way functions like factorization of large integers. Incorporating quantum physics concepts into cryptography is the answer, which results in an assessment of quantum cryptography. A unique type of cryptography known as quantum cryptography makes advantage of quantum mechanics to provide complete protection against the transmitted message. Quantum Key Distribution (QKD), a random binary key distribution used in quantum cryptography, enables communication participants to recognize unauthorized listeners. Quantum Key Distribution (QKD) is likely the most advanced quantum technology currently accessible with full stack systems already in use. This projects goal is to develop secure and encrypted communication between the parties with the help of a web application using the BB84 protocol.

Stochastic Gradient Descent long short-term memory based secure encryption algorithm for cloud data storage and retrieval in cloud computing environment

With the increasing rise of distributed system technologies, one of the most pressing problems facing the digital world is ensuring the security of sensitive and confidential data during transport and storage, which is also regarded as one of the most critical difficulties facing cloud computing. Numerous techniques exist for enhancing data security in the cloud computing storage environment. Encryption is the most important method of data protection. Consequently, several accessible encryption strategies are utilized to provide security, integrity, and authorized access by employing modern cryptographic algorithms. Cloud computing is an innovative paradigm widely accepted as a platform for storing and analysing user data. The cloud is accessible via the internet, exposing the data to external and internal threats. Cloud Service Providers (CSPs) must now implement a secure architecture to detect cloud intrusions and safeguard client data from hackers and attackers. This paper combines Stochastic Gradient Descent long short-term memory (SGD-LSTM) and Blow Fish encryption to detect and prevent unauthorized cloud access. User registration, intrusion detection, and intrusion prevention are the three phases of the planned system. The SGD-LSTM classifier predicts cloud data access and prevents unauthorized cloud access. In the data access phase, cloud data access is managed by authenticating the authorized user with the Blowfish encryption algorithm. Comparing the proposed classifier to existing classifiers demonstrates that it detects abnormal access accurately. The experimental outcomes enhanced data security, which can be utilized to protect cloud computing applications. The experimental results of the suggested SGD-LSTM algorithm indicated a high level of protection, as well as a considerable improvement in security and execution speed when compared to algorithms that are often used in cloud computing.

Development of modification of the post-quantum public-key cryptosystem NTRUENCRYPT

This work is devoted to the development of a modification of the post-quantum public-key cryptosystem NTRUEncrypt. Given that two main requirements for modern cryptographic algorithms are resistance to attacks (including quantum attacks) and performance, the developed modification offers an improvement in both aspects. Karatsuba algorithm for fast polynomial multiplication is employed to achieve better performance. The modification also includes additional protection against a chosen ciphertext attack that can be effectively against standard NTRUEncrypt. Performance test of the developed modification confirmed that less time is required for key generation, encryption and decryption in comparison with the classical algorithm. The modified algorithm is then applied to implement an asymmetric encryption system with a graphical user interface that allows establishing communication between two users with resistance to both classical and quantum attacks.

ELLIPTIC CURVE CRYPTOGRAPHY AND ITS PRACTICAL APPLICATION

Elliptic curves are one of the most promising tools for constructing modern cryptographic algorithms. The security of elliptic curve cryptography is based on the complexity of solving the discrete logarithm problem in the group of points of the elliptic curve over a finite field. Elliptic curve cryptography enables two parties communicating over public channel using elliptic curve encryption and signing algorithms. Elliptic curves allow to achieve the same level of security with small key sizes than other asymmetric cryptographic algorithms. The article describes the mathematical apparatus of elliptic curves used for cryptographic purposes, the basic operations in the group of points of elliptic curves, such as addition of points, doubling of a point, and scalar multiplication of a point by a number are given. The steps and principles of the Diffie-Hellman key exchange algorithm (ECDH) and the digital signature scheme (ECDSA) on elliptic curves are considered. An overview of standards establishing recommendations and requirements for the use of elliptic curves in cryptographic systems is provided. The advantages of elliptic curve cryptography compared to traditional asymmetric algorithms, such as smaller key sizes, computational speed, and efficient use of resources, are analyzed. Potential threats and vulnerabilities of cryptographic algorithms based on elliptic curves are discussed. The main practical application areas of cryptographic algorithms on elliptic curves, including network security, cryptocurrency operations, message exchange, the Internet of Things, and government institutions are investigated. Examples of popular standardized curves (Curve25519, Curve448, secp256k1) that have been tested and recommended by specialized organizations such as NIST are given.

STUDY OF THE CRYPTOGRAPHIC STRENGTH OF THE S-BOX OBTAINED ON THE BASIS OF EXPONENTIATION MODULO

This article presents one of the main transformations of symmetric block ciphers used to protect confidential information, a new method for obtaining a non-linear S block, and an analysis of the results obtained. The S-box obtained by this method can be used as a non-linear transformation in block cipher algorithms to protect confidential data transmitted over an open channel. In most well-known works in the field of analysis and synthesis of modern block symmetric ciphers, S-box is used as a mathematical apparatus for cryptographic Boolean functions. In this case, each S-box is represented by a set of composite Boolean functions whose properties characterize the efficiency of the nonlinear substitution node. Substitution nodes for modern symmetric primitives, including key unfolding functions, are usually implemented as replacement tables. Considering that in most modern block symmetric ciphers for introducing round keys, the encryption algorithm uses a linear operation (bitwise addition modulo 2), S-blocks are the only elements responsible for the cryptographic stability of block encryption algorithms. The required number of rounds of block symmetric ciphers is selected taking into account the results of the cryptographic analysis performed, provided that the properties of S-boxes are specified. As the main criteria and performance indicators, the balance and nonlinearity of composite Boolean functions are used; strict avalanche criterion (SAC), propagation criterion; algebraic degree; the value of the autocorrelation function. In this article, a study was made of the nonlinearity and strict avalanche criterion (SAC) of the S-box used in the block symmetric encryption algorithm. The results of the study were compared with the S-boxes of modern cryptographic algorithms and showed good results.

To the Problems of the National State Recognition System Improving

Introduction. A rapid increase in the number of objects that simultaneously take part in combat operations in the air requires improvement of systems for recognizing military objects both in terms of qualitative and quantitative indicators. This requires the development of appropriate algorithms for identifying new-generation "friend-foe" objects. Such algorithms can be based on various methods of information security, in particular symmetric and asymmetric cryptographic algorithms and other methods of cryptography. The purpose of the article is to survey modern systems of state recognition of objects (SSRO), identify their shortcomings and provide recommendations for their elimination. Results. The requirements for SSRO as a system for processing, transmitting, securing information and identifying objects based on cryptography and computer security methods are defined. Common and distinctive features for civil and military identification systems are highlighted. The advantages and disadvantages of the existing SSRO are shown. Recommendations are formulated to address the shortcomings of the existing SSRO. An example of a stand and a hardware and software basis for studying SSRO algorithms with backup channels is given. Conclusions. Eliminating the shortcomings of the SSRO and improving the level of its reliability will require the implementation of the following organizational and technical measures. 1. Replacing the current state recognition system with a more modern one, which will support more modern cryptographic algorithms and a larger number of recognition objects. Adding support for radio tag recognition (RF tags). 2. Support for recognition lines in various directions, including "ground – UAV", "plane – tank", "plane – UAV" and others. Adding support for the NATO standard – STANAG 4579, adopted in 2001, and others. 3. Using of broad-spectrum signals to reduce the probability of detection and interception, as well as a number of signal-code structures and a working frequency grid. Keywords: Friend-or-Foe, object identification, cryptography, backup channels.

Distance Enhancement of Quantum Cryptography through MANET

In the modern technology world, the cryptographic techniques are plays a major role. There are so many modern cryptographic algorithms are used to secure information through message transformation. Quantum cryptography evolved from the merging of physics and cryptography to reduce the threat that encryption encounters. It is one of the emerging fields in the computer technology. The primary objective of quantum cryptography research is to develop cryptographic algorithms and protocols that are resistant to quantum computer attacks and increase the communication distance. The various quantum cryptography protocols are demonstrated, as well as how this technology has led to the establishment of secure communication between sender and the receiver through using of MANET. We will look at the properties of quantum cryptography and the benefits of MANET it can provide in the future internet. One of the best ways for increasing the distance of message transmission over the internet is to use MANET in the field of quantum cryptography. An Ad hoc on demand distance vector (AODV) is a routing protocol for Mobile Ad hoc networks

Ідентифікація технічних об’єктів в спеціальних мережах за принципом “свій–чужий”

Introduction. In recent years, military conflicts are moving to a fundamentally new level of development, which is associated with the widespread use of geographically distributed large groups of remotely controlled robotic systems, the rapid growth of information volumes, a significant increase in the speed of its processing, instant messaging to increase situational awareness, management, rapid response, etc. Purpose. The article is devoted to solving an urgent scientific problem — the development of an algorithm for state identification of military objects and personnel. The problems of using modern cryptographic algorithms for state identification, which use data obtained by other stations of the air defense system and radio intelligence, combined in a special network, are considered. Results. A new encryption key exchange protocol and a rationale for choosing a cryptographic algorithm that can be used in real-time systems with low computational performance are proposed. To ensure the stability of the use of electronic warfare tools, it is proposed to use software-defined radio stations based on programmable logic matrices as a hardware basis, since they allow changing the type of signal-code structures, which also applies frequency ranges without replacing radio engineering blocks. Conclusions. With the increase in the number of remotely controlled military equipment objects on the battlefield, the problem of positioning military personnel and equipping them with network communication means requires a review of the methods and algorithms used for state recognition. The paper proposes a new algorithm for state identification of objects and identification of military personnel using symmetric cryptographic algorithms and the use of a secure Protocol for exchanging information received from the network of the Armed Forces of Ukraine. This approach can potentially increase the performance and quality of the identification system.

Selection of Sampling Keys for Cryptographic Tests

Abstract The keys of modern cryptographic algorithms have an enormous size, so the testing of the algorithm performance for all key combinations, will take practically an infinite time. To avoid this, the sampling method is used, where a much smaller number of keys is tested and then the estimation of the algorithm performance for all the keys is calculated with a predetermined sampling error. For each sampling key, an output sample of the algorithm must be generated and tested. Therefore, in order to have sampling results as close as possible to the real performance of the algorithm, the key question is whether the selection of the keys should be random or it must follow some rules. If the selection of the keys is completely random, there is a high probability that the tests will not find some "weak" or "equivalent" keys, which give non-random or similar outputs and therefore reduce the total number of active keys. But if the sampling keys are selected with some specific criteria, there is a much greater probability of detecting any weak or equivalent key. In this study an optimal key selection methodology is proposed, which combines the random and the non-random key selection. Keywords: Cryptography, Data encryption, Communication security, Computer security, Data security, Information security.

Sampling methods for cryptographic tests

Modern cryptographic algorithms have an enormous key diversity, therefore the procedures for the testing of the algorithm strength for all the keys, will take practically an infinite time. To avoid this, the sampling method must be used, in which a much smaller number n of the total key combinations N is tested, and then the performance of the algorithm for all the keys is calculated with a predefined sampling error. For each sampling key n, a cipher output (sample) is produced and the critical questions are how many samples must be tested and how large must be the size of each sample. The general rule is that, the sampling error is decreased as the number of the samples is increased. But since the tests must be executed in an acceptable time, the above rule should be considered together with some additional factors, such as the type of the cryptographic cipher, the kind and the size of the plain information and the available computer power. In this study the interrelations of all the above factors are examined and applicable solutions are proposed. Keywords: Cryptography, Data encryption, Communication security, Computer security, Data security, Information security.

О криптографических свойствах S-блоков

The article is devoted to the study of cryptographic properties of S-boxes. S-box is a function that accepts n bits at the input, converts them according to a certain algorithm and returns m bits at the output. n and m are not necessarily equal. S-boxes are one of the main components of modern cryptographic algorithms that determine their nonlinearity. To protect cryptographic algorithms from various types of attacks, S-boxes must meet a number of criteria. The purpose of this work is to study the existing cryptographic properties of S-boxes, which will allow us to further analyze the existing criteria that S-boxes must meet and make a reasonable choice of a set of criteria for optimal S-boxes. This article provides an overview of the main properties of S-boxes that are important in the formation of optimality criteria. Differential uniformity, difference distribution table, nonlinearity, linear distribution table, algebraic degree, algebraic immunity, algebraic complexity, avalanche effect, strict avalanche effect, distance to strictly avalanche effect, completeness, linear structures, balancedness, correlation immunity, bit independence criterion, propagation criterion, period, number of fixed points and opposite fixed points, cycles, inversions, increases, boomerang connection table, boomerang difference table are considered. The existing methods of generating S-boxes with the necessary optimal characteristics are also considered.

Nonlinearity of Many-Valued Logic Component Functions of Modern Cryptographic Algorithms S-boxes

Block symmetric cryptographic algorithms are the essential and inalienable element of any information security system. The main component of block symmetric cryptographic algorithms is the S-box, which largely determines the speed and cryptographic quality of the entire cryptographic transformation. The rapid development of cryptanalysis methods, including the development of quantum computers, requires a more careful research of all possible representations of nonlinear elements of block symmetric cryptographic algorithms. In view of the fact that in addition to the mathematical apparatus of Boolean functions used today to estimate the cryptographic quality of S-boxes, a cryptanalyst can apply the mathematical apparatus of functions of many-valued logic, which makes relevant the task of researching and comparing the cryptographic quality of S-boxes of modern cryptographic algorithms, represented by functions of many-valued logic. This paper presents a research and comparative analysis of nonlinear transformations of the cryptographic algorithms AES, Kalyna, BelT, and Kuznechik when represented by functions of many-valued logic. It was found that only the nonlinear transformation of the BelT cryptographic algorithm is characterized by growth when represented by many-valued logic functions, while the Kalyna cryptographic algorithm demonstrates the greatest decrease in nonlinearity when represented by 16-functions among the cryptographic algorithms researched. The results obtained in the paper indicate a significant unused reserve of cryptographic quality, which can be used in the design of new cryptographic algorithms and their structural elements.

Chaos-based Cryptography: A Brief Look Into An Alternate Approach to Data Security

The present scale of computing inevitably demanded increased level of data security, which is the concern of cryptography. Security of the cipher depends on the strength of the key and the algorithm used to generate the keys. Many modern cryptographic algorithms are based on Number Theory, but in recent years an alternative approach has been studied which is based on Chaos Theory. Many properties of chaotic systems such as nonlinearity, randomness, and sensitivity to initial conditions bear resemblance to those required by cryptography such as diffusion and confusion. Implementations of chaos-based cryptosystems have been proposed by other researchers and yet the strength of these systems from a cryptographic point of view has not been thoroughly considered. This paper discusses the appeal of chaos-based cryptography, some of the researches already done, and the challenges that this approach faces to be established as a fully secure method for data security.

SYNTHESIS METHOD OF TERNARY BENT-FUNCTIONS OF THREE VARIABLES

Context. Such perfect algebraic constructions of many-valued logic as ternary bent-functions and their truth tables which are called as 3-bent-sequences, are used very often in modern cryptographic algorithms, in particular, in pseudorandom sequence generators. However, today there are no methods for synthesizing the ternary bent-functions class for a number of variables greater than two, which significantly limits the ability to scale the number of protection levels of the of pseudorandom sequence generators based on the ternary bent-functions. This circumstance generates the task of developing methods for the synthesis of ternary bent-functions, which is solved in this paper for the case of ternary bent-functions of three variables. The object of this research is the process of efficiency increasing of the cryptographic algorithms based on the functions of many-valued logic.Objective. The purpose of the paper is to construct a method for the synthesis of the set of ternary bent-functions of three variables.Method. The mathematical apparatus of the Reed-Muller transform (algebraic normal form) was used as the basis of the proposed constructive method for the synthesis of ternary bent-functions of three variables. So, on the basis of the established properties of the algebraic normal form of ternary bent-functions and limited enumeration, the search for ternary bent-functions up to affine terms is performed, after which we apply the procedure of reproduction.Results. As a result of using of the proposed method for the synthesis of ternary bent-functions of three variables, 155844 3-bentsequences were found up to an affine term, while the cardinality of the full set of found 3-bent-sequences is 12623364. The research performed made it possible to determine that in this set there are 3-bent-sequences of six different weight structures, on the basis of which 12 different triple sets can be compiled for use in pseudorandom sequence generators. A scheme for a cryptographically stable pseudorandom sequence generator based on the found set of 3-bent-sequences of length N = 27 is proposed. It is shown that the protection levels number of such a generator of pseudorandom sequences is 41 7.041 10    which is comparable with the protection levels number of modern block symmetric cryptographic algorithms, for example, AES-128.Conclusions. The further development of modern cryptographic algorithms, in particular, cryptographically stable pseudorandom sequence generators, is largely based on the use of perfect algebraic constructions of many-valued logic. For the first time, a constructive method for the synthesis of ternary bent-functions of three variables is proposed. For the found set of ternary bent-functions, the distribution of weight structures is found, and the possible triple sets are established. Based on the constructed set of ternary bentfunctions, a pseudorandom sequence generator scheme is proposed that has a protection levels number that is comparable with modern block symmetric cryptographic algorithms. We note that the constructed class of ternary bent-functions can also be used for the synthesis of cryptographically strong S-boxes, codes of constant amplitude, as well as error correction codes. As an actual area of further research, we can note the development of methods for the synthesis of ternary bent-functions of a larger number of variables.

Testing of code-based pseudorandom number generators for post-quantum application

Recent advances in quantum computing based on new principles and phenomena of quantum mechanics show that quantum cryptanalysis of modern cryptographic algorithms can become real in the coming years. For example, according to the forecasts of the US National Institute of Standards and Technology (NIST) in the next decade, quantum cryptanalysis of most asymmetric cryptosystems used today will be available. For this reason, NIST announced a contest of post-quantum (i.e., resistant to quantum cryptanalysis) cryptographic algorithms for directional encryption, electronic signature, and key encapsulation. In the coming years, standardization of the selected algorithms and their early implementation is expected. Obviously, other cryptographic algorithms, for example, pseudorandom number generators based on solving complex theoretical problems (discrete logarithm, factorization, etc.), will also be subject to further revision. These generators must also be replaced by reliable and safe algorithms suitable for use even in the conditions of the possible application of quantum cryptanalysis (i.e., in the post-quantum period). This paper is devoted to the study of provably secure generators whose resistance is based on the complexity of solving the syndrome decoding problem. This structure allows the generators to keep the resistance to both classical cryptanalysis and cryptanalysis using quantum computing. The design features of classic code-based generator representative proposed by Fisher and Stern are presented, and a new generator scheme is proposed to overcome the drawback of its predecessor, such as a reduced practical maximum period length, by using a linear feedback shift register. Within this paper Results of heuristic testing of the above-mentioned generators is conducted in terms of the sequence period, the speed of sequence generation, the cryptographic resistance of the generators and the possibility of their use in the post-quantum period.

Quantum Advantage and the Y2K Bug: A Comparison

The quantum advantage helps speed up computations in many areas. However, quantum computer power can also be leveraged to break modern cryptographic algorithms. To maintain the cryptoagility of software, we must prepare for the era of quantum advantage now.

Rotating Disk Cryptosystem: RDC

Cryptography is a hot and active topic, it plays a crucial role in many aspects nowadays, from internet banking and e-commerce to email and web-based business processes. An important area of research today is to test the security of cryptosystems. A cryptographic system is safe as long as no one could not break it. Modern cryptographic algorithms are based on mathematical problems, known to be difficult, so breaking the security of a cryptosystem requires the solution of a such problem, as in the case of RSA, which is based on the factorization problem in number theory. This paper proposes a symmetric-key cryptosystem named Rotating Disk Cryptosystem and is denoted as RDC used for encryption and decryption of text as well as images which is based on chaotic function and the factorization problem.

Ensuring Cybersecure Telemetry and Telecommand in Small Satellites: Recent Trends and Empirical Propositions

With the advent of a large number of small satellites in the orbit performing critical missions, securing ground/space infrastructure against cyberattacks has become a blazing issue amongst operators and policymakers. In this paper, we provide up-to-date analysis on the recent advances, existing, and future trends in small satellite cybersecurity, considering the advent of new policies and architectures, implementation of modern cryptographic algorithms, and prospects of quantum cryptographic techniques. We explore the performance of selected encryption schemes in the cyberphysical space of small satellites, using throughput, memory footprint, security, and energy consumption as key performance metrics. We propose an open-source cybersecurity analysis platform in the context of small satellites and have found out that the 128 bit Advanced Encryption Standard (AES) is most suitable for securing small satellite telemetry/telecommand channel. We have also investigated possibilities of telemetry compression, proposing a modified Consultative Committee for Space Data Systems telemetry/telecommand packet format to incorporate compression and encryption, and have found simple Huffman coding to be suitable. In order to improve the resilience of ground infrastructure against cyberattacks, a redundant array of ground station elements is recommended to be architected.

Energy Efficient Encryption Algorithm for Low Resources Devices

Saving energy is one of the most challenging aspects in the wireless network devices. Such devices are connected together to perform a certain task. A well-known example of these structures is the Wireless Sensor Network (WSN). Distributed WSN consists of several spread nodes in a harsh area. Therefore, once network has been established sensors replacement is not a possible option before at least five years which called network lifetime. So, it is a necessity to develop specific energy aware algorithms that could save battery lifetime as much as possible. Security and Privacy are the vital elements which need to be addressed to hold up to the trust of users in WSN environment. Because the majority of modern cryptographic algorithms were designed for desktop/server environments, many of these algorithms cannot be implemented in the constrained devices used by these networks. Symmetric key algorithms are a typically efficient and fast cryptosystem, so it has significant applications in many realms. For a WSN with constraint computational resources, the cryptosystem based on symmetric key algorithms is extremely suitable for such an agile and dynamic environment. Therefore, a Simple Lightweight Encryption Algorithm (SLEA) based on addition and subtraction operations and compact Substitution-boxes (S-boxes) is proposed for wireless networks due to its low energy consumption, simple hardware requirements and suitable level of security. In addition, the algorithm tries to overcome the limitations of both public- and symmetric-key protocols. It relies on a smart version of Feistel structure.

Security and Cryptographic Challenges for Authentication Based on Biometrics Data

Authentication systems based on biometrics characteristics and data represents one of the most important trend in the evolution of the society, e.g., Smart City, Internet-of-Things (IoT), Cloud Computing, Big Data. In the near future, biometrics systems will be everywhere in the society, such as government, education, smart cities, banks etc. Due to its uniqueness, characteristic, biometrics systems will become more and more vulnerable, privacy being one of the most important challenges. The classic cryptographic primitives are not sufficient to assure a strong level of secureness for privacy. The current paper has several objectives. The main objective consists in creating a framework based on cryptographic modules which can be applied in systems with biometric authentication methods. The technologies used in creating the framework are: C#, Java, C++, Python, and Haskell. The wide range of technologies for developing the algorithms give the readers the possibility and not only, to choose the proper modules for their own research or business direction. The cryptographic modules contain algorithms based on machine learning and modern cryptographic algorithms: AES (Advanced Encryption System), SHA-256, RC4, RC5, RC6, MARS, BLOWFISH, TWOFISH, THREEFISH, RSA (Rivest-Shamir-Adleman), Elliptic Curve, and Diffie Hellman. As methods for implementing with success the cryptographic modules, we will propose a methodology which can be used as a how-to guide. The article will focus only on the first category, machine learning, and data clustering, algorithms with applicability in the cloud computing environment. For tests we have used a virtual machine (Virtual Box) with Apache Hadoop and a Biometric Analysis Tool. The weakness of the algorithms and methods implemented within the framework will be evaluated and presented in order for the reader to acknowledge the latest status of the security analysis and the vulnerabilities founded in the mentioned algorithms. Another important result of the authors consists in creating a scheme for biometric enrollment (in Results). The purpose of the scheme is to give a big overview on how to use it, step by step, in real life, and how to use the algorithms. In the end, as a conclusion, the current work paper gives a comprehensive background on the most important and challenging aspects on how to design and implement an authentication system based on biometrics characteristics.