Secure Multiparty AES (full paper)

We propose several variants of a secure multiparty computation protocol for AES encryption. The best variant requires 2200 + 400 255 expected elementary operations in expected 70 + 20 255 rounds to encrypt one 128-bit block with a 128-bit key. We implemented the variants using VIFF, a software framework for implementing secure multiparty computation (MPC). Tests with three players (passive security against at most one corrupted player) in a local network showed that one block can be encrypted in 2 seconds. We also argue that this result could be improved by an optimized implementation. The security requirements are the same as for the underlying MPC scheme.