BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Memento EPFL// BEGIN:VEVENT SUMMARY:Karaoke: Distributed Private Messaging Immune to Passive Traffic A nalysis DTSTART:20190108T100000 DTSTAMP:20260530T053722Z UID:374571876e6fa86b49d8d726700cac2220bb961332a361b25f23aca1 CATEGORIES:Conferences - Seminars DESCRIPTION:David Lazar\nKaraoke is a system for low-latency metadata-priv ate communication. Karaoke provides differential privacy guarantees\, and scales better with the number of users than prior such systems (Vuvuzela a nd Stadium). Karaoke achieves high performance by addressing two challenge s faced by prior systems. The first is that differential privacy requires continuously adding noise messages\, which leads to high overheads. The se cond challenge lies in generating sufficient noise in a distributed system where some nodes may be malicious. This talk focuses on how Karaoke solve s the first challenge using optimistic indistinguishability: in the common case\, Karaoke reveals no information to the adversary\, and clients can detect precisely when information may be revealed (thus requiring less noi se). Our prototype of Karaoke achieves a latency of 6.8 seconds for 2M use rs which is 5x to 10x better than Vuvuzela and Stadium.\n\nDavid Lazar is a graduating PhD student at MIT CSAIL\, advised b y Nickolai Zeldovich. His research in systems security has focused on the problem of metadata privacy: how can two users communicate over the intern et without anyone finding out about it? The systems he's built\, including Vuvuzela\, Alpenhorn\, and Karaoke\, take an approach based on differenti al privacy to provide strong metadata protection without sacrificing perfo rmance. David is in the process of deploying his work at . David is also an aspiring mountain climber and training for the Chic ago Marathon in 2019.\n  LOCATION:BC 420 https://plan.epfl.ch/?room==BC%20420 STATUS:CONFIRMED END:VEVENT END:VCALENDAR