What are the primary differences between stream ciphers and block ciphers in symmetric cryptography?
In the realm of symmetric cryptography, two primary types of ciphers are employed to ensure data confidentiality: stream ciphers and block ciphers. Both types of ciphers utilize the same key for both encryption and decryption processes, yet they operate in fundamentally different ways, each with its own set of advantages, disadvantages, and appropriate use cases.
- Published in Cybersecurity, EITC/IS/CCF Classical Cryptography Fundamentals, Stream ciphers, Stream ciphers, random numbers and the one-time pad, Examination review
How truly random are TRNGs based on random physical processes?
Randomness is a fundamental concept in cryptography, as it plays a important role in ensuring the security of cryptographic systems. True Random Number Generators (TRNGs) based on random physical processes are often used to generate random numbers for cryptographic purposes. These TRNGs aim to produce unpredictable and unbiased random numbers by exploiting the inherent randomness
Why a block cipher can be easily turned into a stream cipher while the opposite is not the case?
A block cipher can be indeed easily turned into a stream cipher while the opposite is not the case. This is due to the fundamental differences between block ciphers and stream ciphers, as well as the properties and requirements of each. To better understand this problem, let's first define what block ciphers and stream ciphers
Is it correct that a stream cipher using a truly random key binary sequence is the unbreakable One-Time Pad cipher?
A stream cipher is a type of encryption algorithm that operates on individual bits or bytes of plaintext and produces a corresponding stream of ciphertext. It is based on the use of a key stream, which is generated by combining a secret key with a random or pseudorandom sequence of bits. The key stream is
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