Rolf Oppliger
Students: Spring 2025, unless noted otherwise, sessions will be virtual on Zoom.
E2EE Messaging: State of the Art and Future Challenges
Sep 17, 2025
Abstract
End-to-end encrypted (E2EE) messaging on the Internet allows encrypted messages to be sent from one sender to one or multiple recipients in a way that cannot be decrypted by anybody else - arguably not even the messaging service provider itself. The protocol of choice is Signal that invokes and puts in place several cryptographic primitives in new and ingenious ways. Besides the messenger of the same name, the Signal protocol is also used by WhatsApp, Facebook Messenger, Wire, and many more. As such, it marks the gold standard and state of the art when it comes to E2EE messaging on the Internet.To make it scalable and useful for large groups, the IETF has also standardized a complementary protocol named messaging layer security (MLS). In this talk, we outline the history of development and mode of operation of both the Signal and MLS protocols, and we elaborate on the next challenges for the future.About the Speaker

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