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- MakaleYalnız künye2025Scopus SJRQ2Innovative nonlinear component generator inspired by squirrel search algorithm
Artuğer, Fırat
The most used approach for data encryption is block cipher. One of the most important structures for block cipher algorithms is undoubtedly s-boxes. The s-box structure used in the AES algorithm contains 256 values. Therefore, obtaining powerful s-boxes is a rather difficult search problem. Because the search space is very large (256!). In this study, a new method based on squirrel search algorithm (SSA) is proposed to overcome this problem. The proposed method is displacement-based. In an s-box taken at the entrance, stronger s-box structures are sought by changing the location of the elements. The most important innovation in this study is that the elements to be displaced in the s-box were selected with the positioning states of the SSA. The chaotic Gompertz map was used for the initial population. Four different s-boxes were produced with the method developed thanks to the effective positioning states of SSA. As the fitness function, the nonlinearity value, which is the most important evaluation criterion of an s-box structure, was used. The proposed four s-box structures increased up to 110 nonlinearity values after only 4500 iterations. Here, it has been shown that the algorithm can be effective in all s-boxes by generating four different s-boxes. Considering these results, it has been determined that the proposed method gives more effective results than most methods in the literature.
AtıfScopus1WoS1OpenAlex2
İncele - MakaleAçık Erişim2025Scopus SJRQ1An efficient 2D hyper chaos and DNA encoding-based s-box generation method using chaotic evolutionary improvement algorithm for nonlinearity
Garipcan, Ali Murat; Aydin, Yılmaz; Özkaynak, Fatih
In this study, an innovative substitution box (s-box) method is proposed, which combines the complexity and unpredictability of chaotic systems with the natural randomness and security features of Deoxyribonucleic Acid (DNA) encoding, in response to the increasing security requirements in the field of modern cryptography. This method, based on the integration of a two-dimensional (2D) hyper-chaotic Vincent map (VM) and DNA encoding techniques, aims to produce secure and high-performance s-boxes. To evaluate the reliability of the s-boxes, fundamental cryptographic criteria such as nonlinearity (NL), strict avalanche criterion (SAC), differential probability (DP), linear approximation probability (LAP), and bit independence criterion (BIC) are considered. Additionally, a novel chaos-based evolutionary optimization algorithm is proposed to optimize the NL criterion of the s-boxes. This algorithm offers a cost-effective and highly efficient alternative compared to classical metaheuristic methods, providing a balanced structure between security and performance. Experimental findings and comparison results demonstrate that the proposed s-boxes offer effective and reliable solutions for modern cryptographic applications, such as secure data transmission and storage. From a broader perspective, the study makes a meaningful contribution to the literature in the field of data security by presenting a high-performance s-box design meeting the security requirements of cryptographic systems and is resilient against current threats.
AtıfScopus25WoS26OpenAlex23İncele - MakaleAçık Erişim2024Scopus SJRQ1A new algorithm to generate aes-like substitution boxes based on sine cosine optimization algorithm
Artuğer, Fırat; Özkaynak, Fatih
Symmetric encryption approaches are generally used for data encryption. One of the basic requirements for symmetric encryption algorithms to provide security is strong s-box structures. Because s-box is a nonlinear unit in these encryption algorithms and provides the requirement called confusion. In this article, a new technique is developed to produce effective s-boxes like the 16*16 s-box structure used in the AES algorithm. In the proposed method, the sine cosine algorithm (SCA), one of the recently developed optimization algorithms, is used. SCA is a suitable option for generating strong s-boxes because of its strong randomness and ease of implementation. The proposed method first uses a logistic map to generate the initial population. Then, the nonlinearity value is optimized with the help of the sine cosine algorithm. The proposed method reaches the highest nonlinearity value (112) by relocating 126 values in the s-box structure produced initially. Looking at the results, it is seen that the proposed method gives better results than other optimization-based s-box creation methods. This new method has significant potential to improve the security of symmetric encryption algorithms and make data encryption processes stronger.
AtıfScopus19WoS22OpenAlex24İncele - MakaleYalnız künye2024Scopus SJRQ2A new S-box generator algorithm based on chaos and cellular automata
Artuğer, Fırat
S-boxes are very important structures for encryption algorithms. For S-boxes to be strong, they should not be as linear as possible. Obtaining an S-box with high nonlinearity is a difficult problem. For this reason, it has attracted the attention of researchers for many years. In this study, cellular automata logic was used to overcome this problem. A chaotic tent map was used for the initial population. Then, in this weak S-box, the elements were replaced with their neighbors, and the nonlinearity value was checked. When this value increased, the S-box was transferred to the next generation. With the proposed algorithm, an S-box structure with a nonlinearity value of 110.5 was obtained. This value surpasses most studies in the literature. In addition, it has been proven because of the analysis that the proposed S-box also provides other performance criteria.
AtıfScopus6WoS8OpenAlex7İncele - MakaleYalnız künye2024Scopus SJRQ2A Method for Designing Substitution Boxes Based on Chaos with High Nonlinearity
Artuğer, Fırat
Cryptography aims to design algorithms for the protection of important data transmitted over unsecured networks. These algorithms encrypt the data and render it incomprehensible even if it is captured by enemies. Today’s data encryption standard is the AES algorithm. The most important and nonlinear unit in the AES algorithm is the s-box structure. The S-box provides the mixing process in the algorithm, that is, the confusion. An s-box structure with a high nonlinearity value greatly increases the security against various attacks. Therefore, s-box is of vital importance in an encryption algorithm. When we look at the literature, chaos-based s-box structures are frequently used. However, the nonlinearity value of s-boxes produced with chaos is low. In this article, a new, fast, and very simple method is proposed to increase the nonlinearity value of chaos-based s-box structures. In the proposed method, the nonlinearity value is calculated by changing the places of the elements respectively. When the nonlinearity value increases, the s-box is updated, and the next element is passed. In this way, many iterations are not looked at in vain. This saves a lot of time. As a result of the analysis, it has been proven that the s-box structure obtained by the proposed method is cryptographically strong and has a high nonlinearity value. It is thought that the proposed method will provide many advantages for future cryptography applications.
AtıfScopus9WoS7OpenAlex8İncele - MakaleYalnız künye2024Scopus SJRQ1A novel algorithm based on DNA coding for substitution box generation problem
Artuğer, Fırat
Substitution boxes are very important for cryptographic structures. But getting an 8-bit strong s-box is a difficult problem. To address this problem, a new approach is proposed in this study. DNA chains are used in the proposed approach. First of all, a weak s-box is obtained with the help of a chaotic map. Then, a DNA chain is formed with the same chaotic map. In this study, 2000-long DNA chains were produced. Then, two random values consisting of four components are determined from these DNA chains, and these values are addressed to the s-box structure. By changing the places of these values, the s-box structure is improved up to a certain iteration. In this study, 10,000 iterations were examined, and three different strong s-boxes were obtained by using three different DNA chains. The nonlinearity values of these s-box structures were observed as 110.25, 110.5, and 110.75, respectively. The proposed study has proven to work effectively with effective results in three different chains. In addition, it has been proven as a result of the analysis that the proposed s-box structures also have other cryptographic features. The proposed algorithm has surpassed many s-box generation philosophies in the literature. In addition, the proposed algorithm will provide serious gains to cryptographic structures that will be developed in the future.
AtıfScopus21WoS22OpenAlex24İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2A new post-processing approach for improvement of nonlinearity property in substitution boxes
Artuğer, Fırat; Özkaynak, Fatih
The main reason that makes chaos theory attractive for cryptology studies is the unpredictable nature of chaotic systems. However, the fact that the statistical and cryptographical properties of cryptographic primitives based on the values obtained as a result of the electronic circuit implementation of a chaotic system are not as good as the designs based on mathematical transformations has occupied the agenda of researchers. One of the most striking examples of this problem in practical applications is substitution-box (s-box) structures. While the nonlinearity value is 112 for s-box designs based on mathematical transformations, this value is in the range of 103–106.75 for s-box designs based on random (chaotic) transformations. Thanks to the post-processing algorithm proposed in this study, it has been shown that this problem can be resolved and the nonlinearity values of chaos-based s-box structures can be improved up to 111.5. It is thought that the proposed post-processing algorithm may have various potential contributions not only to improve the nonlinearity criterion of s-box structures but also to other information security applications such as cryptographic random number generators in future studies.
AtıfScopus19WoS13OpenAlex16İncele - MakaleAçık Erişim2024Scopus SJRQ2Strong s-box construction approach based on Josephus problem
Artuğer, Fırat
There are two basic requirements for symmetric encryption algorithms. The first of these is diffusion. The second and most important is confusion. In these algorithms, this requirement is usually met by s-box structures. Therefore, s-box structures must be strong. So, a cryptographically good s-box will make the encryption algorithm difficult to crack. However, obtaining a strong s-box is a rather difficult problem. In this study, Josephus circle logic is used to solve this problem. Initially, with a random s-box structure, the elements are replaced according to their Josephus positions, and the s-box is made stronger. In the proposed algorithm, according to the Josephus logic, the elements that kill each other are replaced and this process continues until one element remains. The last 30 surviving elements are replaced with all elements. In this way, three different s-boxes were obtained. In two of them, the nonlinearity value was 110.5, and in one of them, the nonlinearity value was 110.75. Fixed points in the proposed s-box structures were identified and eliminated. In addition, it has been proven because of the analysis that the obtained s-box structures also meet other cryptographic requirements. In addition to leaving behind most studies in the literature, the proposed method will also provide strong s-box structures for encryption algorithms to be built in the future.
AtıfScopus15OpenAlex12İncele - MakaleYalnız künye2023Scopus SJRQ2A New S-box Generator Algorithm Based on 3D Chaotic Maps and Whale Optimization Algorithm
Artuğer, Fırat
Encryption provides security in cases such as storing confidential information or transmitting it over a network. Today, block cipher algorithms are generally used for encryption. Undoubtedly, one of the most important units of block cipher algorithms to ensure confidentiality is substitution box (s-box) structures. Because s-boxes are nonlinear structures, making the algorithm resistant to differential cryptanalysis. Therefore, the higher the nonlinearity value of the s-box, the stronger it will be. In this study, a new algorithm is proposed to generate s-boxes with high nonlinearity value. In the proposed algorithm, Lorenz and Chua systems, which are 3D chaotic maps, are used for the initial population. The s-boxes produced with these chaotic maps were then increased to 110.5 using the whale optimization algorithm (WOA). WOA is one of the important optimization algorithms developed in recent years and was used for the first time in s-box production in this study. Looking at the results of the analysis, the proposed method has outstripped most of the other existing studies, thanks to effective 3D chaotic maps and WOA.
AtıfScopus44WoS38OpenAlex45İncele - MakaleAçık Erişim2022Scopus SJRQ1SBOX-CGA: substitution box generator based on chaos and genetic algorithm
Artuğer, Fırat; Özkaynak, Fatih
What makes artificial intelligence techniques so remarkable in the field of computer science is undoubtedly their success in producing effective solutions to difficult computational problems. In particular, metaheuristic optimization algorithms are a unique example of using artificial intelligence techniques to generate approximate solutions to problems that cannot be solved in polynomial time, called NP. Obtaining a substitution box (s-box) structure that will satisfy the desired requirements in cryptography is an example of these NP problems. In the literature, it is a hot topic to optimize the s-box structures obtained from chaotic entropy sources with heuristic algorithms to improve their cryptographic properties. The study with the highest nonlinearity value (110.25) based on optimization algorithms to date has been published in 2020. In this study, a method with a higher nonlinearity value than the algorithms previously proposed in the literature is developed. It has been shown that the nonlinearity value can be increased to 111.75. These results will be a basis for new research on the chaos-based s-box literature and will motivate new studies to develop alternative optimization algorithms in the future to obtain s-box structures based on the random selection equivalent to the AES s-box.
AtıfScopus47WoS35OpenAlex49İncele