A comparison of physical random number generators

Abstract

Good random number generators (RNGs) are required for many applications in science and industry. Random numbers can be created in two ways: with a computer algorithm known as a pseudo-random number generator (PRNG), or by measuring physical phenomena which behave randomly, such as quantum mechanical or chaotic systems. However, PRNGs are deterministic in nature and cannot produce truly random output, while physical RNGs can. Three physical RNGs were constructed: a Chua circuit, an electrical circuit which exhibits chaos; an avalanche circuit, which produces a noisy electrical signal; and a radioactive decay counter. Each RNG produced output in the form of ASCII files containing 0s and 1s. The randomness of the data was assessed using the open source statistical test suite rngtest.