1,283 research outputs found

    Fast, parallel and secure cryptography algorithm using Lorenz's attractor

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    A novel cryptography method based on the Lorenz's attractor chaotic system is presented. The proposed algorithm is secure and fast, making it practical for general use. We introduce the chaotic operation mode, which provides an interaction among the password, message and a chaotic system. It ensures that the algorithm yields a secure codification, even if the nature of the chaotic system is known. The algorithm has been implemented in two versions: one sequential and slow and the other, parallel and fast. Our algorithm assures the integrity of the ciphertext (we know if it has been altered, which is not assured by traditional algorithms) and consequently its authenticity. Numerical experiments are presented, discussed and show the behavior of the method in terms of security and performance. The fast version of the algorithm has a performance comparable to AES, a popular cryptography program used commercially nowadays, but it is more secure, which makes it immediately suitable for general purpose cryptography applications. An internet page has been set up, which enables the readers to test the algorithm and also to try to break into the cipher in

    Building Secure and Fast Cryptographic Hash Functions Using Programmable Cellular Automata

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    Cryptographic hash functions have recently brought an exceptional research interest. With the increasing number of attacks against the widely used functions as MD5, SHA-1 and RIPEMD, the need to consider new hash functions design and conception strategies becomes crucial. In this paper, we propose a fast and efficient hash function using programmable cellular automata that are very suitable for cryptographic applications due to their chaotic and complex behavior derived from simple rules interaction. The proposed function is evaluated using several statistical tests, while obtained results demonstrate very admissible cryptographic properties such as confusion/diffusion capability and high sensitivity to input changes. Furthermore, the hashing scheme can be easily implemented through software or hardware, so it provides very competitive running performances

    OPRACOWANIE I BADANIA KRYPTOGRAFICZNYCH FUNKCJI SKRÓTU (HASH) NA PODSTAWIE DWUWYMIAROWYCH AUTOMATÓW KOMÓRKOWYCH

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    Software solution for cryptographic hash functions based on sponge construction with inner state implemented as two-dimensional cellular automata (CA) has been developed. To perform pseudorandom permutation in round transformation function several combinations of CA rules 30, 54, 86, 150 and 158 have been proposed. The developed hashing mechanism provides effective parallel processing, ensures good statistical and scattering properties, enables one to obtain hash of a varying length and reveals strong avalanche effect.Za pomocą oprogramowania zostały opracowane kryptograficzne funkcje skrótu (hash) na podstawie gąbki kryptograficznej, której stan wewnętrzny został zrealizowany w postaci dwuwymiarowych automatów komórkowych (KA). W celu implementacji permutacji pseudolosowych zaproponowano kombinację zasad obróbki CA 30, 54, 86, 150 i 158 w celu realizacji funkcji transformacji rundy. Opracowany mechanizm haszowania pozwala na skuteczne przetwarzanie równoległe, zapewnia jakościowe charakterystyki statystyczne i rozproszenia, pozwala na otrzymanie skrótu o zmiennej długości i ujawnia stabilny efekt lawinowy

    Investigations of cellular automata-based stream ciphers

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    In this thesis paper, we survey the literature arising from Stephan Wolfram\u27s original paper, “Cryptography with Cellular Automata” [WOL86] that first suggested stream ciphers could be constructed with cellular automata. All published research directly and indirectly quoting this paper are summarized up until the present. We also present a novel stream cipher design called Sum4 that is shown to have good randomness properties and resistance to approximation using linear finite shift registers. Sum4 is further studied to determine its effective strength with respect to key size given that an attack with a SAT solver is more efficient than a bruteforce attack. Lastly, we give ideas for further research into improving the Sum4 cipher

    An optimized 128-bit cellular automata-based hash function for authentication of data at rest and in transit

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    The cryptographic hash functions are the most fundamental cryptographic concept. These functions are used as basic building blocks for digital signatures and message authentication. Boolean functions are the core of hash functions. These functions are expected to provide pseudo-randomness as well as input sensitivity. Cellular automata are a form of Boolean function that exhibits strong cryptography properties as well as chaotic behavior. This paper proposes a hash function, designed on the principle of cellular automata. The proposed algorithm is secure and meets the requirements for a successful hashing scheme. The hash function has strong statistical and cryptographic characteristics, according to the findings of the avalanche test and the National Institute of Standards and Technology (NIST) Statistical Test Suite. The modularity of different operations of this algorithm makes it suitable for a high-capacity processing environment to produce efficient performance

    Image Encryption Using Meitei Lock Sequence Generated from Hash Functions

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    Proposed here is a secure image encryption scheme based on generalized Vigenere cipher and Meitei Lock Sequence (MLS) generated from standard hash functions. MLS is a unique random sequence of any length greater than 2 generated from a non-negative array having two or more elements. It is unique in the sense that no two arrays can generate the same sequence however close or similar the two arrays are. In other words, when there is any slight change in any of the input array, the generated MLS’s are drastically different. Also, the length of the sequence can be as infinitely long. These properties make MLS a good key string for a secure encryption scheme. SHA(Secure Hashing Algorithm) or any hash code generator has desirable feature which can be used for generation of MLS. In a hash code generator, it produces unique fixed length sequence from any input string, if there is any slight change in the input, the generated output will be totally different. This feature is made used of  in generating an MLS of any desired length for use in the proposed image  encryption scheme. Experimental results show that the proposed encryption scheme is a secure encryption scheme. The correlation coefficient between the original image and encrypted images are negligibly small indicating that there is no trace of original image information in the encrypted image. Also, the correlation coefficients between the original image and decrypted images with wrong passwords which are close to the encryption password are also negligibly small. These show the tightness of the key system in the encryption scheme. 

    An Adaptive Image Encryption Scheme Guided by Fuzzy Models

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    A new image encryption scheme using the advanced encryption standard (AES), a chaotic map, a genetic operator, and a fuzzy inference system is proposed in this paper. In this work, plain images were used as input, and the required security level was achieved. Security criteria were computed after running a proposed encryption process. Then an adaptive fuzzy system decided whether to repeat the encryption process, terminate it, or run the next stage based on the achieved results and user demand. The SHA-512 hash function was employed to increase key sensitivity. Security analysis was conducted to evaluate the security of the proposed scheme, which showed it had high security and all the criteria necessary for a good and efficient encryption algorithm were met. Simulation results and the comparison of similar works showed the proposed encryptor had a pseudo-noise output and was strongly dependent upon the changing key and plain image.Comment: Iranian Journal of Fuzzy Systems (2023

    Blockchain-Enabled On-Path Caching for Efficient and Reliable Content Delivery in Information-Centric Networks

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    As the demand for online content continues to grow, traditional Content Distribution Networks (CDNs) are facing significant challenges in terms of scalability and performance. Information-Centric Networking (ICN) is a promising new approach to content delivery that aims to address these issues by placing content at the center of the network architecture. One of the key features of ICNs is on-path caching, which allows content to be cached at intermediate routers along the path from the source to the destination. On-path caching in ICNs still faces some challenges, such as the scalability of the cache and the management of cache consistency. To address these challenges, this paper proposes several alternative caching schemes that can be integrated into ICNs using blockchain technology. These schemes include Bloom filters, content-based routing, and hybrid caching, which combine the advantages of off-path and on-path cachings. The proposed blockchain-enabled on-path caching mechanism ensures the integrity and authenticity of cached content, and smart contracts automate the caching process and incentivize caching nodes. To evaluate the performance of these caching alternatives, the authors conduct experiments using real-world datasets. The results show that on-path caching can significantly reduce network congestion and improve content delivery efficiency. The Bloom filter caching scheme achieved a cache hit rate of over 90% while reducing the cache size by up to 80% compared to traditional caching. The content-based routing scheme also achieved high cache hit rates while maintaining low latency
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