Games for extracting randomness

Randomness is a necessary ingredient in various computational tasks and especially in Cryptography, yet many existing mechanisms for obtaining randomness suffer from numerous problems. We suggest utilizing the behavior of humans while playing competitive games as an entropy source, in order to enhance the quality of the randomness in the system. This idea has two motivations: (i) results in experimental psychology indicate that humans are able to behave quite randomly when engaged in competitive games in which a mixed strategy is optimal, and (ii) people have an affection for games, and this leads to longer play yielding more entropy overall. While the resulting strings are not perfectly random, we show how to integrate such a game into a robust pseudo-random generator that enjoys backward andforward security. We construct a game suitable for randomness extraction, and test users playing patterns. The results show that in less than two minutes a human can generate 128 bits that are ...

• Type: Conference
• Year: 2009
• Where: SOUPS
• Authors: Ran Halprin, Moni Naor
• Keywords: Competitive Games, Entropy Source, Randomness, Security Privacy, SOUPS 2009