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arXiv · 2103.11240

Round and Communication Balanced Protocols for Oblivious Evaluation of Finite State Machines

Rafael Dowsley·Caleb Horst·Anderson C. A. Nascimento
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Abstract

We propose protocols for obliviously evaluating finite-state machines, i.e., the evaluation is shared between the provider of the finite-state machine and the provider of the input string in such a manner that neither party learns the other's input, and the states being visited are hidden from both. For alphabet size $|\Sigma|$, number of states $|Q|$, and input length $n$, previous solutions have either required a number of rounds linear in $n$ or communication $\Omega(n|\Sigma||Q|\log|Q|)$. Our solutions require 2 rounds with communication $O(n(|\Sigma|+|Q|\log|Q|))$. We present two different solutions to this problem, a two-party one and a setting with an untrusted but non-colluding helper.

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Rafael Dowsley, Caleb Horst, Anderson C. A. Nascimento. 2021-03-20. Round and Communication Balanced Protocols for Oblivious Evaluation of Finite State Machines. https://arxiv.org/abs/2103.11240

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