Can OFB mode be used as keystream generators?
Output Feedback (OFB) mode is one of the several modes of operation for block ciphers, which allows a block cipher to be used in a way that provides confidentiality by converting it into a stream cipher. This mode is particularly notable for its ability to generate keystreams, making it a suitable candidate for certain cryptographic
Can single bit of ciphertext be influenced by many bit of plaintext in DES?
The Data Encryption Standard (DES) is a symmetric-key algorithm for the encryption of digital data. Developed in the early 1970s and adopted as a federal standard in 1977, DES has been widely used in various applications. One of the critical aspects of DES and other block ciphers is how plaintext bits influence the resulting ciphertext.
Are 7 and 12 equivalent in mode 5 operation
In the context of modular arithmetic, which is a fundamental concept in classical cryptography, the question of whether the numbers 7 and 12 are equivalent in mode 5 operation can be addressed by examining their equivalence under modulo 5. Modular arithmetic is a system of arithmetic for integers, where numbers "wrap around" upon reaching a
What is cryptanalysis?
Cryptanalysis is the study and practice of analyzing information systems to understand hidden aspects of the systems. In the realm of cybersecurity, cryptanalysis specifically refers to the process of deciphering encrypted data without knowledge of the key used in the encryption process. This field is a important aspect of cryptography, which is the broader science
Can public key be used for authentication if the asymmetric relation in terms of complexity in computing keys is reversed?
Public-key cryptography fundamentally relies on the asymmetric nature of key pairs for secure communication, encryption, and authentication. In this system, each participant possesses a pair of keys: a public key, which is openly distributed, and a private key, which is kept confidential. The security of this system hinges on the computational difficulty of deriving the
Are mod 2 addition and subtraction different operations?
In the realm of cybersecurity and classical cryptography, particularly when dealing with modular arithmetic and historical ciphers, understanding the operations of addition and subtraction under different modular bases is important. One commonly encountered base is mod 2, also known as binary arithmetic. In this context, the question arises: are mod 2 addition and subtraction different
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, History of cryptography, Modular arithmetic and historical ciphers
Does DES depends on multiple combinations of diffusion and confusion?
The Data Encryption Standard (DES) is a symmetric-key algorithm for the encryption of digital data. It was developed in the early 1970s and was adopted as a federal standard in the United States in 1977. The algorithm is based on a combination of both diffusion and confusion mechanisms, which are essential principles in classical cryptography
How can stream ciphers encrypt individual bit?
Stream ciphers are a class of symmetric key ciphers in cryptography that encrypt plaintext digits (typically bits) one at a time with a corresponding digit of the keystream. Unlike block ciphers, which encrypt fixed-size blocks of data, stream ciphers operate on continuous streams of plaintext and can encrypt data of arbitrary length. This flexibility makes
Can lsfr be used in practical scenerio?
Linear Feedback Shift Registers (LFSRs) are indeed utilized in a variety of practical scenarios within the field of cybersecurity, particularly in the realm of stream ciphers. To understand their practical applications, it is essential to consider the fundamental principles of LFSRs, their operational mechanisms, and the contexts in which they are employed. An LFSR is
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, Stream ciphers, Stream ciphers and linear feedback shift registers
What is lsfr
A Linear Feedback Shift Register (LFSR) is a key component in the realm of stream ciphers within classical cryptography. It is a shift register whose input bit is a linear function of its previous state. The most commonly used linear function in LFSRs is the exclusive-or (XOR). LFSRs are widely utilized in various applications, including
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, Stream ciphers, Stream ciphers and linear feedback shift registers

