Does the GSM system implement its stream cipher using Linear Feedback Shift Registers?
In the realm of classical cryptography, the GSM system, which stands for Global System for Mobile Communications, employs 11 Linear Feedback Shift Registers (LFSRs) interconnected to create a robust stream cipher. The primary objective of utilizing multiple LFSRs in conjunction is to enhance the security of the encryption mechanism by increasing the complexity and randomness
Did Rijndael cipher win a competition call by NIST to become the AES cryptosystem?
The Rijndael cipher did win the competition held by the National Institute of Standards and Technology (NIST) in 2000 to become the Advanced Encryption Standard (AES) cryptosystem. This competition was organized by NIST to select a new symmetric key encryption algorithm that would replace the aging Data Encryption Standard (DES) as the standard for securing
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, AES block cipher cryptosystem, Advanced Encryption Standard (AES)
What is the public-key cryptography (asymmetric cryptography)?
Public-key cryptography, also known as asymmetric cryptography, is a fundamental concept in the field of cybersecurity that emerged due to the issue of key distribution in private-key cryptography (symmetric cryptography). While the key distribution is indeed a significant problem in classical symmetric cryptography, public-key cryptography offered a way to resolve this problem, but additionally introduced
What is a brute force attack?
Brute force is a technique used in cybersecurity to crack encrypted messages or passwords by systematically trying all possible combinations until the correct one is found. This method relies on the assumption that the encryption algorithm used is known, but the key or password is unknown. In the field of classical cryptography, brute force attacks
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, History of cryptography, Modular arithmetic and historical ciphers
Can we tell how many irreducible polynomial exist for GF(2^m) ?
In the field of classical cryptography, specifically in the context of the AES block cipher cryptosystem, the concept of Galois Fields (GF) plays a crucial role. Galois Fields are finite fields that are extensively used in cryptography for their mathematical properties. In this regard, GF(2^m) is of particular interest, where m represents the degree of
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, AES block cipher cryptosystem, Introduction to Galois Fields for the AES
Can two different inputs x1, x2 produce the same output y in Data Encryption Standard (DES)?
In the Data Encryption Standard (DES) block cipher cryptosystem, it is theoretically possible for two different inputs, x1 and x2, to produce the same output, y. However, the probability of this occurring is extremely low, making it practically negligible. This property is known as a collision. DES operates on 64-bit blocks of data and uses
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, DES block cipher cryptosystem, Data Encryption Standard (DES) - Key schedule and decryption
Why in FF GF(8) irreducible polynomial itself does not belong to the same field?
In the field of classical cryptography, particularly in the context of the AES block cipher cryptosystem, the concept of Galois Fields (GF) plays a crucial role. Galois Fields are finite fields that are used for various operations in AES, such as multiplication and division. One important aspect of Galois Fields is the existence of irreducible
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, AES block cipher cryptosystem, Introduction to Galois Fields for the AES
At the stage of S-boxes in DES since we are reducing fragment of a message by 50% is there a guarantee we don’t loose data and message stays recoverable / decryptable?
At the stage of S-boxes in the Data Encryption Standard (DES) block cipher cryptosystem, the reduction of the message fragment by 50% does not result in any loss of data or render the message unrecoverable or undecryptable. This is due to the specific design and properties of the S-boxes used in DES. To understand why
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, DES block cipher cryptosystem, Data Encryption Standard (DES) - Encryption
With an attack on a single LFSR is it possible to encounter combination of encrypted and decrypted part of the transmission of length 2m from which it is not possible to build solvable linear equations system?
In the field of classical cryptography, stream ciphers play a significant role in securing data transmission. One commonly used component in stream ciphers is the linear feedback shift register (LFSR), which generates a pseudorandom sequence of bits. However, it is important to analyze the security of stream ciphers to ensure that they are resistant to
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, Stream ciphers, Stream ciphers and linear feedback shift registers
In case of an attack on a single LFSR, if attackers capture 2m bits from the middle of transmission (message) can they still calculate configuration of the LSFR (values of p) and can they decrypt in backwards direction?
In the field of classical cryptography, stream ciphers are widely used for encryption and decryption of data. One of the common techniques used in stream ciphers is the utilization of linear feedback shift registers (LFSRs). These LFSRs generate a keystream that is combined with the plaintext to produce the ciphertext. However, the security of stream
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, Stream ciphers, Stream ciphers and linear feedback shift registers