A New Approach to
Practical Active-Secure Two-Party Computation
Jesper Buus Nielsen (
Peter
Sebastian Nordholt (
Claudio
Orlandi (
Sai Sheshank Burra (Indian
Abstract:
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.