Riposte: An Anonymous Messaging System Handling Millions of Users

Authors: H. Corrigan-Gibbs, D. Boneh, and D. Mazières

This paper presents Riposte, a new system for anonymous broadcast messaging. Riposte is the first such system, to our knowledge, that simultaneously protects against traffic-analysis attacks, prevents anonymous denial-of-service by malicious clients, and scales to million-user anonymity sets. To achieve these properties, Riposte makes novel use of techniques used in systems for private information retrieval and secure multi-party computation. For latency-tolerant workloads with many more readers than writers (e.g. Twitter, Wikileaks), we demonstrate that a three-server Riposte cluster can build an anonymity set of 2,895,216 users in 32 hours.

IEEE Symposium on Security and Privacy 2015, pp. 321-338.

Full paper: pdf

Related papers: Slides available here.