A Binomial Crossover Based Artificial Bee Colony Algorithm for Cryptanalysis of Polyalphabetic Cipher

Cryptography is one of the common approaches to secure private data and cryptanalysis involves breaking down a coded cipher text without having the key. Cryptanalysis by brute force cannot be accepted as an effective approach and hence, metaheuristic algorithms performing systematic search can be applied to derive the optimal key. In this study, our aim is to examine the overall suitability of Artificial Bee Colony algorithm in the cryptanalysis of polyalphabetic cipher. For this purpose, using a number of different key lengths in both English and Turkish languages, basic Artificial Bee Colony algorithm (ABC) is applied in the cryptanalysis of Vigenere cipher. In order to improve the ABC algorithm\u27s convergence speed, a modified binomial crossover based Artificial Bee Colony algorithm (BCABC) is proposed by introducing a binomial crossoverbased phase after employed bee phase for a precise search of global optimal solution. Different keys in various sizes, various cipher texts in both English and Turkish languages are used in the experiments. It is shown that optimal cryptanalysis keys produced by BCABC are notably competitive and better than those produced by basic ABC for Vigenere cipher analysis

Analisa Algoritma Ciphers Transposition: Study Literature

Technological developments allow the sending and storage of data can be done quickly, easily, practically, and safely. One security used uses cryptographic techniques. Cryptography is a technique of converting original text (plaintext) into secret text (ciphertext) using cryptographic algorithms (ciphers) or what is called the encryption process. The decryption process is the process of converting data encoded into original data. One of the cryptographic algorithms is the Cipher Transposition Algorithm. The analysis aims to determine the characteristics and application of the Transposition Cipher. The method used in this study by means of Study Literature, analyzes previous research from journals related to the Transposition Cipher Algorithm. The results are in the form of a view using the study literature method and knowing the characteristics and application of the Cipher Transposition algorithm and analyzing trends in previous studies. Kata Kunci : Cryptography, Algorithms, Cipher Transposition, Study literatur

Analisa Algoritma Ciphers Transposition: Study Literature

Technological developments allow the sending and storage of data can be done quickly, easily, practically, and safely. One security used uses cryptographic techniques. Cryptography is a technique of converting original text (plaintext) into secret text (ciphertext) using cryptographic algorithms (ciphers) or what is called the encryption process. The decryption process is the process of converting data encoded into original data. One of the cryptographic algorithms is the Cipher Transposition Algorithm. The analysis aims to determine the characteristics and application of the Transposition Cipher. The method used in this study by means of Study Literature, analyzes previous research from journals related to the Transposition Cipher Algorithm. The results are in the form of a view using the study literature method and knowing the characteristics and application of the Cipher Transposition algorithm and analyzing trends in previous studies. Kata Kunci : Cryptography, Algorithms, Cipher Transposition, Study literatur

Breaking Data Encryption Standard with a Reduced Number of Rounds Using Metaheuristics Differential Cryptanalysis

This article presents the author’s own metaheuristic cryptanalytic attack based on the use of differential cryptanalysis (DC) methods and memetic algorithms (MA) that improve the local search process through simulated annealing (SA). The suggested attack will be verified on a set of ciphertexts generated with the well-known DES (data encryption standard) reduced to six rounds. The aim of the attack is to guess the last encryption subkey, for each of the two characteristics Ω. Knowing the last subkey, it is possible to recreate the complete encryption key and thus decrypt the cryptogram. The suggested approach makes it possible to automatically reject solutions (keys) that represent the worst fitness function, owing to which we are able to significantly reduce the attack search space. The memetic algorithm (MASA) created in such a way will be compared with other metaheuristic techniques suggested in literature, in particular, with the genetic algorithm (NGA) and the classical differential cryptanalysis attack, in terms of consumption of memory and time needed to guess the key. The article also investigated the entropy of MASA and NGA attacks

Implementasi vigenere cipher 128 dan rotasi bujursangkar untuk pengamanan teks

Information that can be in the form of text, image, audio, and video, is a valuable asset that needs to be secured from unauthorized parties. This research aims to study the implementation of Vigenere cipher 128 (VC-128) and square rotation to secure text information. The square rotation is applied to increase the security of the encryption results obtained from VC-128. The randomness of the rotation results was measured using Shannon entropy based on the distance between characters, and the Avalanche Effect measured changes in the encryption results compared to the original text. The square rotation can increase the randomness of the VC-128 encryption results, as indicated by an increase in entropy values. The highest increase in entropy of 34.8 % occurs in repetitive texts with the square size that produces optimal entropy was a 9x9 medium-size square. The Avalanche effect for each test data shows inconsistent results ranging from 44.5 % to 49 %.Informasi merupakan aset berharga yang keamanannya perlu dilindungi dari pihak-pihak yang tidak berhak. Menurut bentuknya, informasi dapat berbentuk teks, citra, audio dan video. Penelitian ini bertujuan untuk melindungi informasi yang disimpan dalam bentuk teks. Metode yang digunakan adalah Vigenere cipher 128 (VC-128) dan rotasi bujursangkar. Rotasi bujursangkar digunakan untuk meningkatkan keamanan dari hasil enkripsi yang diperoleh dari VC-128. Keacakan hasil rotasi diukur menggunakan entropi Shannon berdasarkan jarak antar karakter, sedangkan efek Avalanche digunakan untuk mengukur perubahan hasil enkripsi dibandingkan dengan teks aslinya. Hasil penelitian menunjukkan bahwa rotasi bujursangkar mampu meningkatkan keacakan hasil enkripsi VC-128 yang ditunjukkan dengan adanya peningkatan nilai entropi. Peningkatan entropi tertinggi sebesar 34,8 % terjadi pada teks berulang dengan ukuran bujursangkar yang menghasilkan entropi optimal adalah bujursangkar berukuran sedang, yaitu 9×9. Nilai efek Avalanche untuk setiap data uji memberikan hasil yang tidak konsisten, berkisar antara 44,5 % hingga 49 %

Kriptoanaliz problemlerinin çözümünde evrim stratejisi uygulaması

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Bu çalışmada, Kriptografi ve Kriptanaliz üzerinde duruldu ve çeşitli algoritmalar uygulandı. Optimizasyon, geometri ve diferansiyel hesabın iyileştirilmesini uygulayan en yaşlı matematiksel tiplerden biridir, fakat şimdi problemleri çözmek için bilimsel ve mühendislik tarafından uygulanan en iyi algoritmalardan biridir. Günümüzde, optimum özümü bulmak için optimizasyon problemi uygun şekilde tanımlanmalıdır, daha sonra optimum özüm ilgili Matematiksel yaklaşım kullanılarak bulunabilir. Stokastik algoritmalar için, Sezgisel ve Meta-heuristik olmak üzere iki tanıtıcı optimizasyon tekniği türü vardır. En yaygın kullanılan Meta-heuristics, Sürü zekası (swarm intelligence) ve evrimsel algoritmalar'dır (evolutionary algorithms). Bu araştırma, üç farklı algoritma uyguladı: Evrim Stratejisi, uygunluk Fonksiyonu ve Sütun Transferi Şifreleri. Aynı şekilde, araştırmanın temel amacı, Evrim Stratejisini uygulayarak Sütun Transferi Şifrelemelerini deşifre etmektir. Ayrıca, çalışma, Kriptografi (Sütun Transferi Şifreleri) ve Kriptanaliz (uygunluk fonksiyonu ile Evrim stratejisi) içeren bir uygulama uyguladı uygulama şifreleme (Kriptografi) düz metni ve son olarak şifre metnini deşifre ederek (Kriptanaliz) kullandı. Sütunlu Taşıma Şifreleri, düz metinleri 13 anahtar uzunluğuyla şifrelemektedir. Evrim Stratejisi Algoritması anahtarı ve düz metni bulmaya ve en sonunda şifre metnini hızlı bir şekilde deşifre etmeye çalışır böylece ES, şifreli metnin bigramlarını (iki harfli) ve trigramları (üç harfli) toplamak için geliştirilmiş fitness fonksiyonunu kullanır. Bulgulara göre, çalışma, tüm şifre metinlerini, projede açıklandığı üzere, daha önce uygulanan diğer algoritmalara kıyasla daha etkili ve daha kısa bir sürede deşifre etti.In this study, the Cryptography and Cryptanalysis are focused on them and applied various algorithms. Optimization is one of the most aged mathematical types which applied the improvement of the geometry and differential calculus, but now it's one of the best algorithms applied by scientific and engineering to solve problems. At present, to find the optimum solution the optimization problem has to be defined suitably, then the optimum solution can be found using relevant Mathematical approach. For stochastic algorithms, there are two familiar types of optimization techniques, Heuristic and Meta-heuristic. the most widely used Meta-heuristics are Swarm Intelligence and Evolutionary Algorithms. This research applied three different algorithms, Evolution Strategy combined with Fitness Function and Columnar Transposition Ciphers. Likewise, the main objective of the study is to decipher the Columnar Transposition Ciphers by applying Evolution Strategy. Moreover, the study applied an application which contain Cryptography (Columnar Transposition Ciphers) and Cryptanalysis (Evolution Stratgey with fitness function), the application is encrypting (Cryptography) the plain text and finally deciphering (Cryptanalysis) the cipher text. The Columnar Transposition Ciphers is encrypting the plain text using with 13 key length. The Evolution Strategy Algorithm attempts to find the key and the plain text and finally deciphering the cipher text quickly, so ES uses improved fitned fitness function to gather the bigrams (two letters) and trigrams (three letters) of cipher text. According to the findings the study deciphered all the cipher texts effectively and less time than all the other algorithms previously applied, as explained insdie the project

Algorytmy metaheurystyczne w kryptoanalizie szyfrów strumieniowych

Metaheuristic algorithms are general algorithms allowing to solve various types of computational problems, usually optimization ones. In the dissertation, new versions of selected metaheuristic algorithms were developed: Tabu Search and Ant Colony Optimization algorithms. They have been adapted to solve the problem of cryptanalysis of stream ciphers, which are an important element of data protection processed and stored in information systems. Attempts to hide information from unauthorized persons have a long history. As early as the 5th century BC there was a simple Atbash substitution cipher among the Hebrew scholars. Although a lot has changed since then, and the art of encrypting information has undergone a significant transformation, the issue of confidentiality of communication is still important. Encryption is used wherever protection of transmitted or stored data, especially in information systems, is of key importance. Encryption is used when talking on the phone or logging in via the Internet to a bank account. It is also of great importance in the military. Encryption is an issue with a long history, still important and topical. The proposed Tabu Search and Ant Colony Optimization algorithms adapted to cryptanalysis were tested using three stream ciphers: RC4, VMPC and RC4+. This enabled the development of an attack independent of the design of the cipher itself, assuming that the internal state of the cipher can be represented as a permutation of numbers from a given range. For all proposed metaheuristic algorithms, four types of fitness functions have been tested, three of which are original ones. The original fitness functions enabled achieving better results for all three analysed metaheuristic algorithms compared to a function known from the literature. Each of the proposed algorithms were tested in terms of the impact of parameters values on the results they achieved. Also the results achieved by all three metaheuristic algorithms were compared to one another. The results obtained during cryptanalysis of smaller and full versions of the analysed ciphers with the use of Tabu Search were compared with the results obtained by other metaheuristic algorithms, showing that Tabu Search leads to better results than other metaheuristics. The results obtained using the Tabu Search algorithm were also compared to attacks known from the literature on selected stream ciphers. The results of the experiments indicate that for the VMPC and RC4+ ciphers, the proposed cryptanalysis algorithm using Tabu Search may be better than the cryptanalysis algorithms known so far. The results achieved by other metaheuristic algorithms considered were not as good as for Tabu Search, although it cannot be ruled out that further enhancement of these algorithms could improve the results

Molten steel temperature prediction using a hybrid model based on information interaction-enhanced cuckoo search

This article presents a hybrid model for predicting the temperature of molten steel in a ladle furnace (LF). Unique to the proposed hybrid prediction model is that its neural network-based empirical part is trained in an indirect way since the target outputs of this part are unavailable. A modified cuckoo search (CS) algorithm is used to optimize the parameters in the empirical part. The search of each individual in the traditional CS is normally performed independently, which may limit the algorithm’s search capability. To address this, a modified CS, information interaction-enhanced CS (IICS), is proposed in this article to enhance the interaction of search information between individuals and thereby the search capability of the algorithm. The performance of the proposed IICS algorithm is first verified by testing on two benchmark sets (including 16 classical benchmark functions and 29 CEC 2017 benchmark functions) and then used in optimizing the parameters in the empirical part of the proposed hybrid prediction model. The proposed hybrid model is applied to actual production data from a 300 t LF at Baoshan Iron & Steel Co. Ltd, one of China's most famous integrated iron and steel enterprises, and the results show that the proposed hybrid prediction model is effective with comparatively high accuracy

How digital data are used in the domain of health: A short review of current knowledge

In the era of digitalization, digital data is available about every aspect of our daily lives, including our physical and mental health. Digital data has been applied in the domain of healthcare for the detection of an outbreak of infectious diseases, clinical decision support, personalized care, and genomics. This paper will serve as a review of the rapidly evolving field of digital health. More specifically, we will discuss (1) big data and physical health, (2) big data and mental health, (3) digital contact tracing during the COVID-19 pandemic, and finally, (4) ethical issues with using digital data for health-related purposes. With this review, we aim to stimulate a public debate on the appropriate usage of digital data in the health sector