Jesper Buus Nielsen (
Sebastian Nordholt (
Sai Sheshank Burra (Indian
We propose a new approach to practical two-party computation secure against an active adversary. All prior practical protocols were based on Yao’s garbled circuits. We use an OT based approach and get efficiency via OT extension in the random oracle model. To get a practical protocol we introduce a number of novel techniques for relating the outputs and inputs of OTs in a larger construction.
We also report on an implementation of this approach, that shows that our protocol is more efficient than any previous one: For big enough circuits, we can evaluate more than 20000 Boolean gates per second. As an example, evaluating one oblivious AES encryption (~34000 gates) takes 64 seconds, but when repeating the task 27 times it only takes less than 3 seconds per instance.