Session
Fahrplan 34C3
Resilience

Briar

Resilient P2P Messaging for Everyone
Saal Borg
Torsten Grote
Briar is a peer-to-peer messaging app that is resistant to censorship and works even without internet access. The app encrypts all data end-to-end and also hides metadata by utilizing Tor onion services.

Around the world communication is increasingly monitored and restricted. If communication can not be eavesdropped on, it is often blocked entirely. Less advanced states even block the entire internet nation-wide.

We need to develop tools that are more resilient to these threats. Communication and expression needs to be free. Censorship should not be possible. Even if the internet was taken down, people should still be able to communicate.

This presentation will introduce Briar a resilient messaging app. Its goal is to enable people in any country to create safe spaces where they can debate any topic, plan events, and organize social movements.

Briar does not rely on servers. It connects people directly peer-to-peer and does not care how data is exchanged. Currently, it has plugins for Bluetooth, WiFi and Tor. The latter is used for long-distance communication over the internet and is supposed to not leak metadata.

Briar aims to be secure and easy to use at the same time. An Android app is currently in beta. Support for other platforms is planned.

Since Briar works peer-to-peer, there is no single universal truth in it. Each group of people might have a different view on the available data depending on their connectivity. This opens up some interesting technical and usability problems that you do not encounter in centralized systems where the server is the authority.

Additional information

Type lecture
Language English

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