September 3, 2025
Don Beaver - Fierce Logic
Abstract. We examine how gathering in person to play poker using a physical deck of cards can then support an indefinite stream of secure remote poker games even after the parties scatter to other locations. Is shuffling a 52-card deck enough? How many hands? How many hours? We'll explore the human-scale feasibility of creating a person-to-person unpredictable random correlation stream to last a lifetime.
Technical details. Introduced in 1979 as the inspiration for multiparty secure computations (MPC), Mental Poker enables two players to play games at a distance without having a physical deck of cards at hand, as long as they have reliable trapdoor permutations. These "games" can in fact be any sort of mutual calculation that might otherwise need the assistance of a trusted third party - e.g. secret ballots, Tinder (private unanimous 2-votes), private set intersection, delegation, proof checking, etc. Introduced in 1996, pseudorandom correlation generators (PCGs) made it possible to extend initial correlations (e.g. Oblivious Transfer) using just a one-way function, a substantially weaker technical requirement and a significant efficiency gain. In this setting, OT can be used to generate more OT, and because OT suffices to implement any MPC game, generating MPC resources indefinitely is feasible. In 2025, we start with a bit of poker and extend it to a lot of poker.
Suggested readings: Mental Poker (doi:10.1007/978-1-4684-6686-7_5)
