Efficiency considerations in using semi-random sources

Abstract

Randomness is an important computational resource, and has found application in such diverse computational tasks as combinatorial algorithms, synchronization and deadlock resolution protocols, encrypting data and cryptographic protocols. Blum [Bl] pointed out the fundamental fact that whereas all these applications of randomness assume a source of independent, unbiased bits, the available physical sources of randomness (such as zener diodes) suffer seriously from problems of correlation. A general