Async Group Messaging with Strong Security 🔒

We show for the first time that post-compromise security can be achieved in realistic, asynchronous group messaging systems. We present a design called Asynchronous Ratcheting Trees (ART), which uses tree-based Diffie-Hellman key exchange to allow a group of users to derive a shared symmetric key even if no two are ever online at the same time.
Read this paper in the ACM Digital Library: https://dl.acm.org/citation.cfm?id=3243747