VictorTaelin

Higher-Order Company: Towards an Optimal Computer

What is the true nature of computation?

A hundred years ago, humanity answered that very question, twice. In 1936, Alan invented the Turing Machine, which, highly inspired by the mechanical trend of the 20th century, distillated the common components of early computers into a single universal machine that, despite its simplicity, was capable of performing every computation conceivable. From simple numerical calculations to entire

Nick-Gabe

 const pombify = (phrase) => {
   return phrase
     .split(' ')
     .map((word) => {
       const wordLetters = word.split('')
       return wordLetters
         .map((letter, index) => {
           const charCode = letter.charCodeAt(0);
           const binary = charCode
             .toString(2)

publik-void

Fast MiniMax Polynomial Approximations of Sine and Cosine

SunnyRaj

#!/usr/bin/env bash

sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
sudo apt update

sudo update-alternatives --remove-all gcc
sudo update-alternatives --remove-all g++
sudo apt-get install -y gcc-4.8 g++-4.8 gcc-4.9 g++-4.9 gcc-5 g++-5 gcc-6 g++-6 gcc-7 g++-7

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 10

LaurentMT

Context

This third part is about known and potential attacks against the privacy provided by tools like coinjoin.


Known attacks & weaknesses

- Linkability of inputs and outputs

A good illustration of this attack is Coinjoin Sudoku (see (1) for details).

LaurentMT

Context

In part 1 of this document, we've defined the entropy of a transaction.
This metric is a first good proxy to qualify the degree of privacy provided by a transaction but it fails to detect privacy leaks occuring at lower levels (1).
In this second part, we define 2 complementary fine-grained tools/metrics: the Link Probability of 2 utxos (LP) and the Link Probability Matrix (LPM) of a transaction.


Link Probability of 2 UTXOs

We call Link Probability of a tuple (tx input, tx output) the probability that a link exists between the 2 utxos.

LaurentMT

This document is an attempt to define metrics quantifying the degree of privacy provided by a bitcoin transaction.


Objectives

Definition of metrics measuring the resistance of a transaction to a set of attacks against users privacy.

Attacks considered in the scope of these metrics are:
- Merged Inputs Heuristic: methods identifying the inputs controlled by a same entity
- Coinjoin Sudoku: methods identifying the links existing between the inputs and outputs of a transaction