Outsourcing Computation: The Minimal Refereed Mechanism

Abstract

We consider a setting where a verifier with limited computation power delegates a resource intensive computation task—which requires a TxS computation tableau—to two provers where the provers are rational in that each prover maximizes their own payoff—taking into account losses incurred by the cost of computation. We design a mechanism called the Minimal Refereed Mechanism (MRM) such that if the verifier has (formula presented) time and (formula presented) space computation power, then both provers will provide a honest result without the verifier putting any effort to verify the results. The amount of computation required for the provers (and thus the cost) is a multiplicative (formula presented) S-factor more than the computation itself, making this schema efficient especially for low-space computations.