Faster Secure Two-Party Computation in the Single-Execution Setting

We propose a new protocol for two-party computation, secure against malicious adversaries, that is significantly faster than prior work in the single-execution setting (i.e., non-amortized and with no pre-processing). In particular, for computational security parameter \({\kappa }\) and statistical security parameter \({\rho }\), our protocol uses only \({\rho }\) garbled circuits and \(O({\rho }+ {\kappa })\) public-key operations, whereas previous work with the same number of garbled circuits required either \(O({\rho }\cdot n+{\kappa })\) public-key operations (where n is the input/output length) or a second execution of a secure-computation sub-protocol. Our protocol can be based on the decisional Diffie-Hellman assumption in the standard model.