35th Chaos Communication Congress

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No evidence of communication and morality in protocols: Off-the-Record protocol version 4
2018-12-29 , Borg
Language: English

OTRv4 is the newest version of the Off-The-Record protocol. It is a protocol where the newest academic research intertwines with real-world implementations. It is also one of the first protocols that comes from the global south which makes the political discussion around protocols an urgency. This newest versions also asks us to revisit our definitions around deniability (online and offline) and how important is it to the world. In this talk we will try to start a discussion around the importance of protocols, its political/moral foundations, the real-world implementation of academic ideas, the importance of securely implementing them, the definition of deniability in the current world and the design of OTRv4.


As we know from past revelations, the Internet has become a place where any action is surveilled and recorded. In the light of this, the OTR protocol was created. But it was created long time ago. In the past years, there have been a increased work on cryptographic primitives, and privacy and security notions. But these thoughts have not been incorporated into projects. OTRv4 is the newest version of the Off-The-Record protocol, which tries to incorporate these new ideas. At the same time, OTRv4 is a protocol that challenges the common thinking around protocols as it comes from the global south, and takes moral questions into its design, as Rogaway tried to defined on his "The Moral Character of Cryptographic Work?" paper. Furthermore, OTRv4 tries to update the notion of deniability and why it is important for the world.