2018-11-03 | #cryptography #mathematics #number-theory
Number theory, or higher arithmetic, is a branch of pure mathematics devoted primarily in the study of integers.
Abstract algebra is involved in the study of abstractions such as groups, rings and fields.
2018-09-11 | #distributed-systems
A shorter version of the official Raft whitepaper.
Crash Fault Tolerant (CFT) algorithm for replicated state machines.
Raft primary goal is understandability.
Novel features:
Randomized approaches introduce nondeterminism, but also reduces the algorithm possible state spaces.
2018-05-14 | #programming #tooling
Coverage testing measures the effectiveness of test suites by determining the code coverage. It identifies areas of the code that haven’t been executed, enabling to improve test quality and enhance software reliability.
2018-04-06 | #os-dev #programming #security
BeeOS is a FOSS UNIX-like operating system focused on simplicity and POSIX compliance.
The overall system is composed by four subprojects:
libc)libu)user)kernel)This analysis targets the BeeOS kernel component
2017-11-10 | #encoding #standards
The Basic Encoding Rules for ASN.1 (BER) give one or more ways to represent any ASN.1 value as an octets sequence.
There are three methods to encode an ASN.1 value under BER, the choice of which depends on the type of value and whether the length of the value is known. The three methods are primitive definite-length, constructed definite-length and constructed indefinite-length.
2017-11-07 | #cryptography
Feistel ciphers are a family of symmetric encryption algorithms that use repeated rounds of substitution and permutation operations on blocks of data to provide confidentiality and data integrity.
Popular examples of Feistel ciphers include:
2017-11-07 | #programming #security
The following article is highly inspired by the work of Will Dietz, Peng Li, John Regehr, and Vikram Adve: ‘Understanding Integer Overflow in C/C++’.
The work has been sliced down to the core and amended with some notes.
2017-10-02 | #cryptography #number-theory
The Chinese Remainder Theorem (CRT) is a mathematical theorem that provides an efficient way to solve systems of linear congruences.
Specifically, it states that given a set of integers that are pairwise coprime and a set of remainders modulo those integers, there exists a unique solution, modulo the product of the integers, to the system of congruences.
2017-09-25 | #cryptography
Let’s first try to build a scheme directly from the Fermat’s Little Theorem.
Given a prime number p and a message m < p, we choose two numbers e and
d such that e·d ≡ 1 (mod p-1).
2017-08-19 | #mathematics #number-theory
Given a natural number $n$, the Euler $\varphi$ function, also known as Euler’s Totient, applied to $n$ represents the number of positive numbers less than $n$ that are coprime with $n$.