Tree-Based Ring-LWE Group Key Exchanges with Logarithmic Complexity

摘要

We present the first constant-round, multicast, tree-based Ring-LWE group key exchange protocol with logarithmic communication and memory complexity. Our protocol achieves post-quantum security through a reduction to a Diffie-Hellman-like decisional analogue to the decisional Ring-LWE problem. We also present a sequential, multicast, tree-based Ring-LWE group key exchange protocol with constant communication and memory complexity but a logarithmic number of rounds.