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Cryptography Threats
Published in Nicholas Kolokotronis, Stavros Shiaeles, Cyber-Security Threats, Actors, and Dynamic Mitigation, 2021
Konstantinos Limniotis, Nicholas Kolokotronis
Cryptanalysis is the study of mathematical techniques for attempting to defeat cryptographic techniques [1]. To assess the cryptographic strength of a cryptographic algorithm (also being called cipher), we assume specific capabilities of the attacker or cryptanalyst (regarding her/his knowledge, apart from the encryption algorithm itself); depending on these capabilities, specific general types of cryptanalytic attacks are determined. A ciphertext-only attack is the case which attacker tries to recover the decryption key or plaintext by only observing ciphertext. A known-plaintext attack is one where the attacker in addition knows a part of the plaintext or, more generally, some pairs “plaintext-ciphertext.” The chosen-plaintext attack assumes a more powerful attacker, being able to choose for which plaintexts she/he will be able to learn the corresponding ciphertexts2. In a converse manner, the chosen-ciphertext attack assumes that the attacker is able to choose for which ciphertexts she/he will be able to learn the corresponding plaintexts3.
Fundamental Cryptographic Characteristics of Boolean Functions: A Review
Published in S. Ramakrishnan, Cryptographic and Information Security, 2018
Majid Khan, Syeda Iram Batool Naqvi
Differential cryptanalysis was first presented at Crypto conference in 1990 by E. Biham and A. Shamir as an attack on DES [16]. Heys [15] describes the main principle: “Differential cryptanalysis exploits the high probability of certain occurrences of plaintext differences and differences into the last round of the cipher.” It is a chosen plaintext attack, that means plaintext can be selected and output subsequently calculated in order to derive the key [17]. In this section XOR distribution, linear and differential probability are defined [18,19].
WLAN Security and Defense
Published in Rihai Wu, Xun Yang, Xia Zhou, Yibo Wang, Enterprise Wireless Local Area Network Architectures and Technologies, 2021
Rihai Wu, Xun Yang, Xia Zhou, Yibo Wang
Brute force key cracking, an exhaustive attack method, is a cryptanalytic attack that tries every possible password combination to find the real password. For example, a password that contains only four digits may have a maximum of 10,000 combinations, and can therefore be cracked after a maximum of 10,000 attempts. In theory, it’s just a matter of time that an attacker cracks any password, depending on the security mechanism and password length. In this sense, any authentication mode is vulnerable to brute force attacks.
A Comprehensive Literature of Genetics Cryptographic Algorithms for Data Security in Cloud Computing
Published in Cybernetics and Systems, 2023
Ozgu Can, Fursan Thabit, Asia Othman Aljahdali, Sharaf Al-Homdy, Hoda A. Alkhzaimi
The invention and analysis of protocols that prevent third parties or the general public from accessing private messages is another broad approach to cryptography. This section defines key terms and discusses several elements of cryptography. A cryptographic system is a mechanism used for encryption. Cryptanalysis, sometimes known as "cracking the code," is a way of decrypting data without knowing the encryption methods employed. Cryptanalysts are those who practice cryptanalysis. Cryptology is the area of mathematics that encompasses both cryptography and cryptanalysis (Jakimoski 2016). Modern cryptography synthesizes several fields, including mathematics, computer science, and electrical engineering. Its processes are roughly characterized as Symmetric _Key _Cryptography, Asymmetric_Key_Cryptography, Hash_functions, and Digital_Signatures.
Energy Efficient Lightweight Cryptography Algorithms for IoT Devices
Published in IETE Journal of Research, 2022
Tarun Kumar Goyal, Vineet Sahula, Deepak Kumawat
The general purpose of cryptography is to secure the data (plain text) from cyber-thieves (like called foes, assailants, interceptors). Cyber terrorists are accepted to have complete access to the correspondence between the sender and beneficiary. Cryptanalysis is the process of recovery of the plain text of a message without access to the key. It likewise may discover shortcomings in a cryptosystem that inevitably prompt the past results. In this section, an attempt has been given to get an idea of hardness. Let us see an example of four digit lock having combinations to unlock. Here a digit can be 0–9 so there are 10 possibilities for all n digit. Now discuss about binary numbers (0 and 1). For N bit key size combinations are possible according to brute force. Differential, linear, integral, and impossible differential analyses are most practical in term of data and time complexity. A meet in the middle (MITM) attack is suitable for block ciphers like AES, LED, Picallo, and PRESENT. A biclique cryptanalysis technique is based on MITM attack. The computations for registering discrete logarithms on elliptic curve- the baby step, giant step method, and Pollard's rho method have been borrowed from [4,26] and tabulated in Table 2.
Image encryption using the random FrDCT and the chaos-based game of life
Published in Journal of Modern Optics, 2019
Jianhua Wu, Xingyu Cao, Xifa Liu, Lujuan Ma, Jianping Xiong
In the broadest sense, differential cryptanalysis is the study of how differences in the plaintext can affect the resultant difference in the cipher text. In the experiment, the influence on the output of the one-pixel change in input is investigated. To evaluate the property in resisting differential attacks, two quantities are commonly used, i.e. the number of pixels change rate (NPCR) and the unified average changing intensity (UACI) (36). For an image of size , 256 grey scales, the NPCR and UACI are calculated as: where and , respectively, represent pixel values at of the cipher images with and without one-pixel change in their corresponding plaintext images. is a bipolar defined as: For images with 256 grey scales, the expected values of NPCR and UACI are 99.6094% and 33.4635% (37), respectively. Tests have been performed on images Peppers, Baboon and Fishing boat, and the results are shown in Table 3. With both of the two quantities exceeding expectation, the proposed algorithm is verified to be secure against the differential attacks.